(10+y)(10-y)=

Solution for (10+y)(10-y)= equation:

Simplifying
(10 + y)(10 + -1y) = 0

Multiply (10 + y) * (10 + -1y)
(10(10 + -1y) + y(10 + -1y)) = 0
((10 * 10 + -1y * 10) + y(10 + -1y)) = 0
((100 + -10y) + y(10 + -1y)) = 0
(100 + -10y + (10 * y + -1y * y)) = 0
(100 + -10y + (10y + -1y2)) = 0

Combine like terms: -10y + 10y = 0
(100 + 0 + -1y2) = 0
(100 + -1y2) = 0

Solving
100 + -1y2 = 0

Solving for variable 'y'.

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

Add '-100' to each side of the equation.
100 + -100 + -1y2 = 0 + -100

Combine like terms: 100 + -100 = 0
0 + -1y2 = 0 + -100
-1y2 = 0 + -100

Combine like terms: 0 + -100 = -100
-1y2 = -100

Divide each side by '-1'.
y2 = 100

Simplifying
y2 = 100

Take the square root of each side:
y = {-10, 10}