In the figure attached, the length of line segment CD is...

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In the figure attached, the length of line segment CD is twice the length of line segment BC. The ratio of the area of ΔABC to the area of ΔABD is:

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A) 1:2√2

B) 1:3√3

C) 1:2

D) 1:3

E) 1:4

The OA is D.

I'm confused with this PS question. Please, can any expert assist me with it? Thanks in advanced.

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by [email protected] » Sun Nov 26, 2017 10:04 am
Hi LUANDATO,

We're asked to find the ratio of the areas of triangle ABC to triangle ABD. In this prompt, we're not given ANY of the side lengths, so we can TEST VALUES to get the solution.

Let's TEST...
AB = 2
BC = 2
CD = 4
Area of triangle ABC = (1/2)(2)(2) = 2
Area of triangle ABD = (1/2)(2)(6) = 6

Thus the ratio of the area of ABC to the area of ABD is 2:6 = 1:3

Final Answer: D

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