(4x+9)(4x-9)=

Solution for (4x+9)(4x-9)= equation:

Simplifying
(4x + 9)(4x + -9) = 0

Reorder the terms:
(9 + 4x)(4x + -9) = 0

Reorder the terms:
(9 + 4x)(-9 + 4x) = 0

Multiply (9 + 4x) * (-9 + 4x)
(9(-9 + 4x) + 4x * (-9 + 4x)) = 0
((-9 * 9 + 4x * 9) + 4x * (-9 + 4x)) = 0
((-81 + 36x) + 4x * (-9 + 4x)) = 0
(-81 + 36x + (-9 * 4x + 4x * 4x)) = 0
(-81 + 36x + (-36x + 16x2)) = 0

Combine like terms: 36x + -36x = 0
(-81 + 0 + 16x2) = 0
(-81 + 16x2) = 0

Solving
-81 + 16x2 = 0

Solving for variable 'x'.

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

Add '81' to each side of the equation.
-81 + 81 + 16x2 = 0 + 81

Combine like terms: -81 + 81 = 0
0 + 16x2 = 0 + 81
16x2 = 0 + 81

Combine like terms: 0 + 81 = 81
16x2 = 81

Divide each side by '16'.
x2 = 5.0625

Simplifying
x2 = 5.0625

Take the square root of each side:
x = {-2.25, 2.25}