(2c+6)(2c-6)=

Solution for (2c+6)(2c-6)= equation:

Simplifying
(2c + 6)(2c + -6) = 0

Reorder the terms:
(6 + 2c)(2c + -6) = 0

Reorder the terms:
(6 + 2c)(-6 + 2c) = 0

Multiply (6 + 2c) * (-6 + 2c)
(6(-6 + 2c) + 2c * (-6 + 2c)) = 0
((-6 * 6 + 2c * 6) + 2c * (-6 + 2c)) = 0
((-36 + 12c) + 2c * (-6 + 2c)) = 0
(-36 + 12c + (-6 * 2c + 2c * 2c)) = 0
(-36 + 12c + (-12c + 4c2)) = 0

Combine like terms: 12c + -12c = 0
(-36 + 0 + 4c2) = 0
(-36 + 4c2) = 0

Solving
-36 + 4c2 = 0

Solving for variable 'c'.

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

Add '36' to each side of the equation.
-36 + 36 + 4c2 = 0 + 36

Combine like terms: -36 + 36 = 0
0 + 4c2 = 0 + 36
4c2 = 0 + 36

Combine like terms: 0 + 36 = 36
4c2 = 36

Divide each side by '4'.
c2 = 9

Simplifying
c2 = 9

Take the square root of each side:
c = {-3, 3}