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555-605 (Medium)|   Geometry|      
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If A is 25 kilometers east of B, which is 12 kilometers south of C, wh 01 May 2018, 05:37
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82% (02:07) correct 18% (03:17) wrong based on 87 sessions

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If A is 25 kilometers east of B, which is 12 kilometers south of C, which is 9 kilometers west of D, how far is it. in kilometers. from A to D?


A. \(20\)

B. \(5\sqrt{34}\)

C. \(5\sqrt{41}\)

D. \(10 \sqrt{13}\)

E. \(71\)
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If A is 25 kilometers east of B, which is 12 kilometers south of C, wh 01 May 2018, 16:27
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Bunuel
If A is 25 kilometers east of B, which is 12 kilometers south of C, which is 9 kilometers west of D, how far is it. in kilometers. from A to D?


A. \(20\)

B. \(5\sqrt{34}\)

C. \(5\sqrt{41}\)

D. \(10 \sqrt{13}\)

E. \(71\)
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Now after we draw the diagram the issue becomes simple
Need to find AD. \(AD^2\) = \(AX^2 + XD^2\) = \(16^2 + 12^2\) = \(256+144\) = \(400\)
Hence \(AD = 20\) ......................Hence the answer is A
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If A is 25 kilometers east of B, which is 12 kilometers south of C, wh 01 May 2018, 19:42
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u1983
Bunuel
If A is 25 kilometers east of B, which is 12 kilometers south of C, which is 9 kilometers west of D, how far is it. in kilometers. from A to D?


A. \(20\)

B. \(5\sqrt{34}\)

C. \(5\sqrt{41}\)

D. \(10 \sqrt{13}\)

E. \(71\)


Now after we draw the diagram the issue becomes simple
Need to find AD. \(AD^2\) = \(AX^2 + XD^2\) = \(16^2 + 12^2\) = \(256+144\) = \(400\)
Hence \(AD = 20\) ......................Hence the answer is A
Show more

Same solution. After drawing out the figure and properly labeling the legs of the triangle. Look for a simpler triangle for a quicker calculation...the triangle 12-16-hypotenuse is a 3-4-5 triangle multiplied by 4. Therefore, the hypotenuse is 5 x 4 = 20. Answer choice A.
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If A is 25 kilometers east of B, which is 12 kilometers south of C, wh 24 Oct 2020, 09:29
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