(5r+5)(5r-5)=

Solution for (5r+5)(5r-5)= equation:

Simplifying
(5r + 5)(5r + -5) = 0

Reorder the terms:
(5 + 5r)(5r + -5) = 0

Reorder the terms:
(5 + 5r)(-5 + 5r) = 0

Multiply (5 + 5r) * (-5 + 5r)
(5(-5 + 5r) + 5r * (-5 + 5r)) = 0
((-5 * 5 + 5r * 5) + 5r * (-5 + 5r)) = 0
((-25 + 25r) + 5r * (-5 + 5r)) = 0
(-25 + 25r + (-5 * 5r + 5r * 5r)) = 0
(-25 + 25r + (-25r + 25r2)) = 0

Combine like terms: 25r + -25r = 0
(-25 + 0 + 25r2) = 0
(-25 + 25r2) = 0

Solving
-25 + 25r2 = 0

Solving for variable 'r'.

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

Add '25' to each side of the equation.
-25 + 25 + 25r2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + 25r2 = 0 + 25
25r2 = 0 + 25

Combine like terms: 0 + 25 = 25
25r2 = 25

Divide each side by '25'.
r2 = 1

Simplifying
r2 = 1

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