Question

find the length x.

Explanation:

Step1: Use similar - triangles property

Since the two right - triangles are similar, the ratios of their corresponding sides are equal. The ratio of the vertical sides is equal to the ratio of the horizontal sides. So, $\frac{x}{3.5}=\frac{8}{7}$.

Step2: Solve for x

Cross - multiply the equation $\frac{x}{3.5}=\frac{8}{7}$ to get $7x = 8\times3.5$. Then $7x=28$, and $x = \frac{28}{7}=4$.

Answer:

4