(y-1)(y+1)=0

Solution for (y-1)(y+1)=0 equation:

Simplifying
(y + -1)(y + 1) = 0

Reorder the terms:
(-1 + y)(y + 1) = 0

Reorder the terms:
(-1 + y)(1 + y) = 0

Multiply (-1 + y) * (1 + y)
(-1(1 + y) + y(1 + y)) = 0
((1 * -1 + y * -1) + y(1 + y)) = 0
((-1 + -1y) + y(1 + y)) = 0
(-1 + -1y + (1 * y + y * y)) = 0
(-1 + -1y + (1y + y2)) = 0

Combine like terms: -1y + 1y = 0
(-1 + 0 + y2) = 0
(-1 + y2) = 0

Solving
-1 + y2 = 0

Solving for variable 'y'.

Move all terms containing y to the left, all other terms to the right.

Add '1' to each side of the equation.
-1 + 1 + y2 = 0 + 1

Combine like terms: -1 + 1 = 0
0 + y2 = 0 + 1
y2 = 0 + 1

Combine like terms: 0 + 1 = 1
y2 = 1

Simplifying
y2 = 1

Take the square root of each side:
y = {-1, 1}