Question

Which equation results from taking the square root of both sides of (x – 9)2 = 81? x – 9 = ±9 x + 9 = ±9 x + 3 = ±9 x – 3 = ±9

Answer 1

a. x-9=+-9

Explanation:

Answer 2

The answer is x - 9 = ±9.

When you take the square root of (x - 9)², you simply remove the exponent. 81 on the other hand has two possible square roots, -9 and 9, hence we always include ± before the square root (i.e. ±9).

Hope this helps.