First, You cross multiply.
(x - 1)(x + 1) = 8
x^2 - 1 = 8
Now subtract 8 from both sides.
x^2 - 9 = 0
x^2 - 9 is a difference between 2 squares.
(x + 3)(x - 3) = 0
For an equation with only multiplying to be equal to 0, one of its factors must be 0.
So either x + 3 = 0 or x - 3 = 0.
So x could be -3 or 3.
The answer is (E).
Hope this helps!
