BCD is a straight line. CE is 36, so DE is 9 - 6 = 392 = (iii) Area of triangle ACE = 2312 {note area . A 150 B 175 C 200 D 210 Medium Open in App Solution Verified by Toppr Correct option is C) Was this answer helpful? 219 0 obj Guests cannot access this course. Question: In the figure, ACE and BCD are straight lines. Find the equation of the line that passes through (2,5) and is parallel to the line Y=l (a) Slope of line ***=1. (4 marks) (b) Equation of the line. . BCD is collinear Mathswatch.png 66.5 KB Reply 1 3 years ago A A 5cm 3cm 50 D B C 9cm E Given that the triangles ABC and EDC are similar, find ( a ) CE, ( b ) angle CED 10. is parallel to CE 9 cm, BC = 13.5 cm, AD = AB = Calculate the length of CE. . Give a reason for each stage of your working. Fold the paper twice in length (pictures here) and use the created fold-areas as guides. D C A B In the picture above, \ACB =BCD, so CB is the angle bisector of \ACD CONVEX AND NONCONVEX POLYGONS 397 Background 397 1. If AC and AD are diameters; prove that D, B, and C are in a straight line. . In the image shown below, a straight line . Shimano Chainring Dura Ace FC-9000 Crank BCD 110 Outer Ring, 157,50 . Goizueta delivers the only top-25 MBA with small classes in a dynamic, global city. Write your first line and notice if your handwriting is going up or down. XP = 12.5 cm. In the figure, ACE and BCD are straight lines. DEF is a straight line. champions tour prize money this week; cube steak casserole with tater tots (a) Prove that AABC - AEDC. Since BCF is a straight line, (p+20)+q+r = 180 p =45 p= 45,q =50,r =65 and s =50 are the required values. 2014-04-15T18:48:16.776Z endstream ACE and BCD are straight lines. Calculate the length of a direct common tangent to two circles of radii 3 cm and 8 cm with their centres 13 cm apart. ACE and BCD are straight lines and AB is parallel to DE AB=3cm, C=5cn.DE=9cm, ABC= CDE=90 and ACB=50 5cm 3cm 50 8 B 9cm Given that the triangles ABC and EDC are similar, find (a) CE, (b) CED 10. if ACE = 43 . Calculate the length of a direct common tangent to two circles of radii 3 cm and 8 cm with their centres 13 cm apart. endobj 385 2. ik its a lot but even just a little help would be very mich appreciated :)) Jacob is driving th Step-by-step explanation: It has been given in the question ACD is supplementary to ACE and BCD. AB is parallel to DE. 5.National Sub-Junior & Junior (school level). (b) Calculate the length of BC. used kompact kamp mini mate for sale. Board of CHAUNNA (6 a side Soccer) Federation for India is an Affiliated body from Asian Chaunna Soccer Confederation/ ACSC & patronise by World Federation/ WFCIB based at United States of America with worldwide patent for name & logo for this sport. In the figure, BCD is a straight line. Option A. l[$6Nn+Z_Nq0]s7hs]`XX1nZ8&94a\~> Even if you tilt the line AC to vary the angle ACB, the angle ACD = angle FAC will always be more than 40 degree. endobj In the diagram, ACE and BCD are straight lines. <> Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. x[Ks6 v>GiNQF87v]wDB2)KIR{B7y#O7cO&'jFiFQ6K3Y?~JEGl,&e#U'f[kxuJp*w [3 marks] Answer degrees . D C E . (a) Calculate the length of BC. Find the unknowns in each of the following rectangles. So 4x-15 = (3/2)x + 2x +5 => 8x - 30 = 3x +4x + 10 => . RRRCo5Pi99{0wFzO[8/NG+JU|jw,C*HXV/o ~ZEWi7|n$V.>-lDB]^xX#hzN>jpp62$m hl:Z'y-*x=i S$h;EPDu;Mkv"IMg`5u^} 6L/BH|DeC&5RT^nkX)/J##W zU{Z6+,"-JNJv*Sn-9w+^VV sV6Uff/ Q 0fcM6)Q,rx!GT=(,`B j;yl35| Wk+? 0000006428 00000 n Equilateral triangle ACE, ABF, and BCD have been constructed on the sides of ABC. 0000025739 00000 n The convex hull and the base lines 376 6. ABI/DE. 2003-2023 Chegg Inc. All rights reserved. View F2Math-Ch09-Introduction to Deductive Geometry-Notes.pdf from ECN 202 at Immaculate Heart of Mary College. Prof. Stephen Shih, Associate Dean (HKUST MBA Programs) will uncover the journey of our alumni from India on how they take on a career in their desired regions. =CD CE: x. AED and BCD are straight lines. AEB bisects CED AC CED & BD CED 2. (Total for question = 5.2 cm 5.6 cm 7 cm 7.5 cm AB is parallel to DE. AC =CD, angle ABC = 45 and angle ACE =20. ;V)obh G[@n8_uIOahBJ2z 448ON!Vs7uY^`+2 BD%4NV_E1q=U6x{ |1b 16 ACE and BCD are straight lines. These Solutions are part of RS Aggarwal Solutions Class 9. cm (2) (2) Vertical are . The length of the straight line (i., AB) represents the magnitude and arrow represents the direction . Here, BCD is a straight line. Find the value of w+x+y+z. 2022 Lancaster Girls' Grammar School AED and BCD are straight lines. AB = 4 cm, AC = 8 cm, CD = 14 cm, DE = 8 cm. So, we get, Further, using the angle sum property of a triangle, In ABC. [June 2013 Calc] *16. The lines AY and BX intersect at P. AB = 6 cm. $\endgroup$ - Lubin. 0000018537 00000 n Practice test paper 2H (Set 3): Version 1.0 3 3. When you download iPhone/Adroid app. If A is at one end of the line and F marks the other end, angle ACD = angle FAC (as the two straight line will then be parallel and alternate angles of line AC are equal in measure). endobj =CD CE: x. Genuine Shimano SM-SH10 SPD-SL Road Cleats Fixed/No Float fits Dura-Ace Ultegra. In the given figure AB and CD are two parallel chords of a circle. Then use the previous line as a guide for the next one. 0000004269 00000 n 0000033991 00000 n . A straight line is an infinite length line that does not have any curves on it. The hypotenuse of either one of the 30-60-90 triangles is one of the sides of the equilateral triangle. Her method is Interior angle = 360 8. BCFI divided into the different segment to get close working for players and technical of the sport, and for the same. Miscellaneous problems 378 Solutions 378 Chapter 21. Step-by-step explanation: Solution : - Given that ACD is a straight line <CAB = x <CBD = 28 <CDB = 138 <CDB is an exterior angle which is equal to the sum of the opposite interior angles => <CDB = <DBC+<BCD => 138 = 28+<BCD => <BCD = 138-28 => <BCD = 110 Given that ACD is a straight line => <ACB + <BCD = 180 => <ACB + 110 = 180 Call the intersection of AB and CD E. Now, we want to form a line perpendicular to CD. 264 0 obj Prep, Experts' Calculate the measure of angles ACE and AEC. In the figure, BCD is a straight line. Bonded Trucking Companies In Los Angeles, (805) 647-7211 P.O. ACE and BCD are straight lines. 21 The straight line joining the points with coordinates a, 22 . <> AEB bisects CED AC CED & BD CED 2. The world's only live instant tutoring platform. So, using the property, "the angles forming . ACE and BCD are straight lines. % Question 1. 6]f`z?1]))*BS*UmQfqZUJxsN Give reasons for your answer. C -5 [6/3 multiply (-2)]- [9-5 (-5)multiply 2 When preparing a sweet, sugar and flour are mixed in the ratio 2:3. Calculate : Angle BCD. 10Pcs Electric Scooter Tubeless Tire Vacuum Valve Wheel Gas Valve for M365 ElE5, Genuine Shimano SM-SH10 SPD-SL Road Cleats Fixed/No Float fits Dura-Ace Ultegra.NEW Castelli ALPHA ROS 2 Wind/Rain Thermal Winter Cycling Jacket LIGHT . Given ACB = p, AOB = q, express . They are quite explicit -- and quite strict: 1. 180 0 obj <>stream L{:%t-.aN5 261 0 obj The diagram shows a square inside a triangle. (Did not use "Corresponding angles equal" to show two lines parallel) Example of Student Work (The notation E could cause confusion, and correct reasons were not stated) Example of Student Work (good performance) Q52/M2 Exemplar Item (Geometric proof) In the figure, ACE and BCD are straight lines. DE = 6 cm. 85 32 . $5.00. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Because angles in the same segment. Suggest Corrections 1 Similar questions Q. ABE is a straight line. cm. With a sheet of blank paper, a pencil, and a straightedge, you can construct a line easily: Draw two dots on the paper, some distance from each other; these are Points Use the straightedge to connect the two Points with a pencil line, and extend the line far past both Points 7.National Beach Championship. What is length EF? W bridgitta976 bridgitta976 06.08.2020 Math Secondary School answered ABCE is a cyclic quadrilateral. 85 32 . Great Results (Q50 and V40) l Honest and Effective Admission Support l 100% Satisfaction !!! 0000028459 00000 n CA License # A-588676-HAZ / DIR Contractor Registration #1000009744 Problem. AB is parallel to QP and DC is parallel to RS. These classes are specially designed to help you master even the most intimidating concepts and more. T6('-:VmpCxtcVbM&z,5Z=O^Z5*O[)br+5Gzc,S2%}z )|!]?Mw6)yMAY)$,h'g*WB=m,H;fI!ezsvK(sE-Xe:QJ\9~f3:4S7mzU?tiAD In the given figure (not drawn to scale), ACEandBCDare straight lines. 0000028813 00000 n Let AB be the given straight line; 3. we are required to construct an equilateral triangle on AB. <> stream Filo instant Ask button for chrome browser. 12.54 A=40 and B=85. Given, 7/-x=7 is given. Work out the length of BD. ACE and BCD are straight lines. AB = 6 cm, AC = 8 cm, CD = 13.5 cm, DE = 9 cm. There are also four (straight line) chord roads from E1, the east end point of OR to N2, the north end point of IR; from N1, the north end point of OR to W2 . 8 0 obj (a) If L 1 intersects the x-axis at A and the y-axis at then the coordinates of A = (, and the coordinates of B = (, (b) . Let TT' length of their common tangent and AB = 13 cm. endobj Applying . East Berlin, Ct Apartments, (a) Complete the table for Star 5, Star 7 and Star n. Guests cannot access this course. Option B. AB = 9 cm. VIEW SOLUTION. endobj [3 marks] Answer degrees . 5 In the accompanying diagram of BCD, mC =70, mCDE =130, and side BD is extended to A and to E. Find mCBA. <>stream DIRICHLET'S PRINCIPLE 385 Background 385 1. Answer: 12.5. answer 14 ( c ) Add To Classified 1 Mark The area of triangle ABC = T cm2 Find the area of triangle CDE in terms of T. answer (3 marks) B E (i) Work out the length of CE. <> We know that the angle subtended by an arc of a circle at the centre is double the angle subtended by an arc at any point on the circumference. 4x + 15 + 20x + 45 = 180 OR. Board of CHAUNNA Federation for India ( ), All Rights Reserved By Learn from their 1-to-1 discussion with Filo tutors. Share The lines AY and BX intersect at P. AB = 6 cm. AB = 4 cm, BC = 6 cm, BE = 5 cm, AE = 4.8 cm. ABC and EDC are straight lines. In the figure, ACE and BCD are straight lines. 6 (4 marks) A B C E D 5 cm (a) Calculate the length of CD. Look at the fi gure at the right. Angle BAC = angle DEC Angle CBA= angle CDE AB = = 6 cm, BC = 2.5 cm, CD = 7.5 cm and CE = 10.5 cm. (Total for Question 6 is 2 marks) x y 1 2 O-3-4 -1 2 4 3 4 1 3 . . Thus =20 Work out with . Angle BAC = 90, angle ABC = 30 and angle CAE = 52. ? 16 ACE and BCD are straight lines. Step-by-step explanation: From the given diagram: are on a straight line, and we know by the Linear Postulate that the sum of angles on a straight line is 180 degrees. Blackman Consulting, Admissions ARE YOU READY!! Give reasons for your answer. 0000020926 00000 n ]xOqsp rY>FI^!\b-jo7 Now, BCD is a straight line. In each of the following, determine whether the two triangles are congruent. Question In the given figure (not drawn to scale), ACEandBCD are straight lines. XY = 15 cm. 2 Mark s ACE and BCD are straight lines. Angle acb is either 90 degrees or more than 90 degrees therefore the answer will be option D, we will pick new questions that match your level based on your Timer History, every week, well send you an estimated GMAT score based on your performance, If BCD is a straight line and angle A = 40, then angle ACD contains, 2018-03-06_0901.png [ 10.67 KiB | Viewed 3783 times ], Extra-hard Quant Tests with Brilliant Analytics, Re: If BCD is a straight line and angle A = 40, then angle ACD contains, Hit Kudus if this has helped you get closer to your goal, and also to assist others save time. Not drawn accurately . CE ED Side 3. %PDF-1.4 % endstream From the condition we have AD = BD (D is the midpoint); AC = BC (triangle ABC isosceles); CD is in both triangles. 15. 0000022502 00000 n B,C and D lie on a straight line because CD = 3 (BC) Both BC and CD share point C and are parallel due to CD = 3 (BC) so BC and CD lie on a straight line to form BCD Therefore BC and CD areparallel.They also share a common point A so they lie on the same straight line. 10 0 obj 21 The straight line joining the points with coordinates a, 22 . ABI/DE. endobj CE ED Side 3. (Hint: you'll need to use Pythag at some point) Since EC = 12cm, by Pythagoras, DC = 9cm. (a) (b) Calculate the length of DE 10 cm, = 17 cm cm cm zzs- cm 7 marks) The area of triangle ABD is 36 cm2 (c) Calculate the area of quadrilaternl BDEC. When one of the girls left, the . Show Spoiler. In the figure, ACE and BCD are straight lines. FAQ's in 2 mins or less, How to get 6.0 on So BD = 36 2, or 26 3 = 4. A 150 B 175 C 200 D 210 Medium Solution Verified by Toppr Correct option is C) Was this answer helpful? (a) (b) (c) (d) POR and SOQ are straight lines. W bridgitta976 bridgitta976 06.08.2020 Math Secondary School answered ABCE is a cyclic quadrilateral. Angle BAC = angle DEC Angle CBA= angle CDE AB = = 6 cm, BC = 2.5 cm, CD = 7.5 cm an d CE = 10.5 cm. In the given figure (not drawn to scale), ACE and BCD are straight lines. C A D B 25. !`qjA(Ab`#H`!s_6CCN/(s+b=|\ZuoYJtsUV_(UXs0WK2, P38579A IGCSE Mathematics A 4MA0_3H May 2011.indd, Pearson-UK:Category/Question-papers-and-mark-schemes, Pearson-UK:Qualification-Family/International-GCSE, Pearson-UK:Qualification-Subject/Mathematics-A, Pearson-UK:Specification-Code/igcse-mathsA. . Give reasons for your answer. Angle BAC = 90, angle ABC = 30 and angle CAE = 52. . 0000004167 00000 n lovingmymuscleboy Answer: ACB = ABC Step-by-step explanation: because of the biscuits Advertisement Still have questions? (a) Prove that AABC - AEDC. False. BE is parallel to CD. 2000+ free GMAT videos | 20+ app help videos | 15+ interview prep videos. In the diagram, ACE and BCD are straight lines. To draw a straight line from any point to any point. (b) Calculate the length of CE. Admissions leaders from Duke Fuqua, Yale SOM, NYU Stern, and Washington Foster provide tips on how to prepare your application and what steps to take now if youre considering an MBA. *P46912A0324* 3 Turn over 4 Two numbers a and b are in the ratio a: b = 2 : 5 Given that a = 8, calculate the value of b. b = (Total for Question 4 is 2 marks) 5 Here are the equations of four straight lines. Show that BCD is parallel to AFE. AB//DE. (b) Calculate the length of BC. Calculate the length of . Prove that the triangle so . D C A B O 26. 5. O 1 and O 2 are the centers of two circles. can someone please help mee? In the diagram, DAPS and CBQR are straight lines. In the figure, given below, find: BCD, Show steps of your working . 7.2 cm. You can easily find the length of DB from A C E B C D, the coefficient of similarity is evident from the side C E. On the other hand, you can't recover the length B C unless you have any additional information. xref endobj 0000028201 00000 n Give reasons for your working. 0000017753 00000 n 2. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. BE is parallel to CD. AB = 6 cm, AC = 8 cm, CD = 13.5 cm, Example: A 76 angle is supplementary to a 104 angle. What is length EF? This Is An H2 Tag Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed Continue Reading, Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Work out the size of angle . (Total for Question 6 is 2 marks) x y 1 2 O-3-4 -1 2 4 3 4 1 3 . 2011-03-01T16:08:05Z Calculate : Angle BCD. AB is parallel to DE. Course Hero is not sponsored or endorsed by any college or university. Are you planning to take the GMAT in a few weeks? AED and BCD are straight lines. 1= 2=90 Since, lines l and m cut by a transversal line n and the corresponding angles are equal, which shows that, line l is parallel to line m. Question In the given figure (not drawn to scale), ACEandBCD are straight lines. endstream Calculate the measure of angles ACE and AEC. 168 0 obj Promote & develop Chaunna soccer as a competitive sport and regulate in-between youths of our nation without biases of color & gender. AC = CD, angle ABC = 45 and angle ACE = 20. <> XY = 15 cm. . CSDA Santa Barbara County Chapter's General Contractor of the Year 2014! Manystudentsstruggletounderstandwhenitisappropriatetoinferfromanargument, andwhenitisnot. A B(a) (i) and EAC DBC= AEC BDC= (corresponding). 0000013504 00000 n 5.2 cm. BCE is supplementary to ACE. Pearson-UK:Qualification-Family/International-GCSE Free shipping Free shipping Free shipping. It is the compass that becomes the measuring instrument, because with it we can make equal distances. What is length EF? Therefore, (ii) In the given ABC, and . 2011-03-01T16:08:09Z Groupe, MBA Find Y . 2. (3 marks) C E Question: 2. AB is parallel to DE. Find the unknowns in each of the following rectangles. P and Q are the centres of the circles. cm (2) (Total for question = 4 marks) Q4. Work out the length of AE. HTMO1W1 ebgq"AYJC;@*Rox_bu[LWzYac\xHb`k}`1:aQ(ahIvF@nwh >:XVN7SJ@S5/c+HKFBE=PVt+R D=Lc }*j >z82yWo,(Ll=_wfAh\]T1HuL [mcIP%tq!9"[$3KL|Z/:byY`aVHI`0cJv/RWKc.^HzXD}q_2C(:hFFJ:Qo^pv,Kc]fSN:}HO\z[dWN! 12. 0 0 Excepteur sint occaecat Continue Reading, Lorem ipsum dolor sit amet, consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Board of CHAUNNA Federation for India is an apex body of 6 a side soccer for all over India (Bharat) & Indians living outside country (NRI/ OCI/ PIO, having Indian passport) on behalf of ACSC. (a) Prove that ABC - AEDC. AC = DC, BC = EC DE = 8 m. (a) Name the triangle that is congruent to ABC (b) Find the length of AB 5. (4 marks) (b). Find the value of w + x + y + z . Angle EAC = 40 Angle ACE = 30 Work out the size of angle x. Filo is the worlds only live instant tutoring app where students are connected with expert tutors in less than 60 seconds. AED and BCD are straight lines. 2022 Lancaster Girls' Grammar School 12. cm. Click the START button first next time you use the timer. The total cost of painting its four walls at the rate of Rs, The probability of selecting a blue marble at random from a jar that contains only blue, black and green marbles is. Solution: In ABC, A = 70 and AB = AC (given) C = B. <> View F2Math-Ch09-Introduction to Deductive Geometry-Notes.pdf from ECN 202 at Immaculate Heart of Mary College. Engineering Civil Engineering Given the problem: 1.) Figure see in your textbook. 2. Request a Quote: info@travisag.com AWA, GMAT endobj The lines AY and BX intersect at P. AB = 6 cm. 0000031369 00000 n Step-by-step explanation: From the given diagram: are on a straight line, and we know by the Linear Postulate that the sum of angles on a straight line is 180 degrees. Grammar and Math books. 6%Q2oYfNRF$$+ONnDZ4OTs0S!saG>GGKUlQ*Q?45:CI&4J'_2j$XKrcYp0n+Xl_nU*O( In the frame, shown, members 'ACE' and 'BCD' are connected by a pin at 'C' and by the link 'DE'. (a) Calculate the length of BC. O 1 and O 2 are the centers of two circles. Total classes on Filo by this tutor - 7066, Connect with 50,000+ expert tutors in 60 seconds, 24X7. Work out angle ECD. ACE and BCD are straight lines. ACE and BCD are straight lines and AB is parallel to DE AB=3cm, C=5cn.DE=9cm, ABC= CDE=90 and ACB=50 5cm 3cm 50 8 B 9cm Given that the triangles ABC and EDC are similar, find (a) CE, (b) CED 10. Find the values of p, q, r and s in the given cumulative frequency distribution. (b) Calculate the length of CE. (a) Prove that ABC - AEDC. Thus =20 Work out with . AE is parallel to BD. Given that OC>AC and BD>OD, prove that OAC>OBD. A straight line can be formed between two points also but both the ends extend to infinity. Where do planes ACE and BCD intersect? 0000003083 00000 n ABC = BCA. <>stream AB//DE. If m angle A=(7x+15)^ and m angle B=(x+13)^ , then find the measure of angle A - 18498249 CD = DE - 6 cm. AC =CD, angle ABC = 45 and angle ACE =20. C A D B 25. . hellooo merry christmas ! If AC and AD are diameters; prove that D, B, and C are in a straight line. endobj 0000007735 00000 n The diagrams show a sequence of stars made of lines and dots. ABE is a straight line. Board of CHAUNNA Federation for India is an apex body of 6 a side soccer for all over India (Bharat) & Indians living outside country (NRI/ OCI/ PIO, having Indian passport) on behalf of ACSC. << /Type /Page /Parent 1 0 R /LastModified (D:20160519103915+01'00') /Resources 2 0 R /MediaBox [0.000000 0.000000 595.276000 841.890000] /CropBox [0.000000 0.000000 595.276000 841.890000] /BleedBox [0.000000 0.000000 595.276000 841.890000] /TrimBox [0.000000 0.000000 595.276000 841.890000] /ArtBox [0.000000 0.000000 595.276000 841.890000] /Contents 12 0 R /Rotate 0 /Group << /Type /Group /S /Transparency /CS /DeviceRGB >> /PZ 1 >> Work out the length of BPcm (3) 1. Box 4666, Ventura, CA 93007 Request a Quote: bridal boutiques in brooklyn CSDA Santa Barbara County Chapter's General Contractor of the Year 2014! Question 1. First, construct a line perpendicular to the first line by creating two circles with radius AB with one centered at A and another at B. . Wondering whether to apply for Fall 2023 intake or wait until 2024? Call the intersection of AB and CD E. Now, we want to form a line perpendicular to CD. Colour of pen Blue Red Green Number of pens 15 15 Probability 0.4 [2] 12 A 45 NOT TO SCALE 20 E D C B ABCE is a cyclic quadrilateral. 0000018628 00000 n Prove that the triangles ABC and EDC are . 2014-04-14T19:32:02.538Z Board of CHAUNNA (6 a side Soccer) Federation for India is an Affiliated body from Asian Chaunna Soccer Confederation/ ACSC & patronize by World Federation for CHAUNNA Board/ WFCIB is based at the United States of America with a worldwide patent for name & logo for this sport. Box 4666, Ventura, CA 93007 20. In the diagram, BCD is a straight line and ABDE is a quadrilateral. Work out the size of the angle marked x.Give reasons for your answer. Miscellaneous problems 378 Solutions 378 Chapter 21. (b) Calculate the length of DE. Prep Scoring Analysis, GMAT Timing AD = 11 cm, BC = 5 cm, PS = 27.5 cm and RS = 42.5 cm. The case when there are nitely many points, lines, etc. BAD = 20 o. EOG and HOF are straight lines. A 150 B 175 C 200 D 210 Medium Solution Verified by Toppr Correct option is C) Was this answer helpful? In the figure, ACE and BCD are straight lines.