Question

In triangles $ABC$ and $ADC$, $\angle BAC = \angle ADC = 90^\circ$. Also, $DC$ is 2 units long and $AC$ is 4 units long. What is the length of $BC$?

Accepted Answer

A. Triangle $ADC$ is similar to Triangle $CAB$ by AAA similarity. $\frac{CD}{CA} = \frac{CA}{CB} \implies \frac{2}{4} = \frac{4}{BC} \implies BC = 8$ units.

Similar Triangles and Side Lengths

Explanation

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