Question

What is the value of a, if a2 – 64 = 0 and a > 0? A) 0 B) 4 C) 8 D) 16

Answer 1

a2 - 64 = 0
a2 = 64
a = 32

32>0

Answer 2

C) 8

Explanation:

Let's solve for:

`a^2 -64=0\\\\a>0`

Add 64 to both sides:

`a^2-64+64=0+64\\\\a^2=64`

Take the square root of both sides

`√(a^2) = √(64) \\\\a=\pm 8`

Therefore, we got two solutions:

`a=8\\\\or\\\\a=-8`

However, since:

`a>0`

The only solution is:

`a=8`