Question

What is the answer to the following: (reference the photo for answer)

a=

Answer options are:

4

6

9

Please show explanation so that I better understand how to get the answer next time! Thank you.

Answer 1

9

Explanation:

To calculate c from the first right angle triangle,

C2 = 36 + 16

C = sqrt(52)

To calculate a from the bigger right angle triangle,

B2 + 52 = (a + 4)2

B2 - a2 = -36 + 8a

A2 + 36 = B2

Solving both by elimination,

A = 72/8

=9