(9c-5)(9c+5)=

Solution for (9c-5)(9c+5)= equation:

Simplifying
(9c + -5)(9c + 5) = 0

Reorder the terms:
(-5 + 9c)(9c + 5) = 0

Reorder the terms:
(-5 + 9c)(5 + 9c) = 0

Multiply (-5 + 9c) * (5 + 9c)
(-5(5 + 9c) + 9c * (5 + 9c)) = 0
((5 * -5 + 9c * -5) + 9c * (5 + 9c)) = 0
((-25 + -45c) + 9c * (5 + 9c)) = 0
(-25 + -45c + (5 * 9c + 9c * 9c)) = 0
(-25 + -45c + (45c + 81c2)) = 0

Combine like terms: -45c + 45c = 0
(-25 + 0 + 81c2) = 0
(-25 + 81c2) = 0

Solving
-25 + 81c2 = 0

Solving for variable 'c'.

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

Add '25' to each side of the equation.
-25 + 25 + 81c2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + 81c2 = 0 + 25
81c2 = 0 + 25

Combine like terms: 0 + 25 = 25
81c2 = 25

Divide each side by '81'.
c2 = 0.3086419753

Simplifying
c2 = 0.3086419753

Take the square root of each side:
c = {-0.555555556, 0.555555556}