Question

Find the value of b.

a=5 and c = 10

A.9.5
B.10
C.9
D.8.7
Please can you explain.

Answer 1

D. 8.7

Explanation:

In order to say anything about the length of b, we must assume the triangle is a right triangle. Then the Pythagorean theorem applies, and we have ...

c² = a² +b²

b² = c² -a² . . . . . subtract a²

b = √(c² -a²) . . . . . . take the square root

b = √(10² -5²) = √(100 -25) = √75

b ≈ 8.7