(4c+5)(4c-5)=

Solution for (4c+5)(4c-5)= equation:

Simplifying
(4c + 5)(4c + -5) = 0

Reorder the terms:
(5 + 4c)(4c + -5) = 0

Reorder the terms:
(5 + 4c)(-5 + 4c) = 0

Multiply (5 + 4c) * (-5 + 4c)
(5(-5 + 4c) + 4c * (-5 + 4c)) = 0
((-5 * 5 + 4c * 5) + 4c * (-5 + 4c)) = 0
((-25 + 20c) + 4c * (-5 + 4c)) = 0
(-25 + 20c + (-5 * 4c + 4c * 4c)) = 0
(-25 + 20c + (-20c + 16c2)) = 0

Combine like terms: 20c + -20c = 0
(-25 + 0 + 16c2) = 0
(-25 + 16c2) = 0

Solving
-25 + 16c2 = 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 + 16c2 = 0 + 25

Combine like terms: -25 + 25 = 0
0 + 16c2 = 0 + 25
16c2 = 0 + 25

Combine like terms: 0 + 25 = 25
16c2 = 25

Divide each side by '16'.
c2 = 1.5625

Simplifying
c2 = 1.5625

Take the square root of each side:
c = {-1.25, 1.25}