(u+4)(u-4)=0

Solution for (u+4)(u-4)=0 equation:

Simplifying
(u + 4)(u + -4) = 0

Reorder the terms:
(4 + u)(u + -4) = 0

Reorder the terms:
(4 + u)(-4 + u) = 0

Multiply (4 + u) * (-4 + u)
(4(-4 + u) + u(-4 + u)) = 0
((-4 * 4 + u * 4) + u(-4 + u)) = 0
((-16 + 4u) + u(-4 + u)) = 0
(-16 + 4u + (-4 * u + u * u)) = 0
(-16 + 4u + (-4u + u2)) = 0

Combine like terms: 4u + -4u = 0
(-16 + 0 + u2) = 0
(-16 + u2) = 0

Solving
-16 + u2 = 0

Solving for variable 'u'.

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

Add '16' to each side of the equation.
-16 + 16 + u2 = 0 + 16

Combine like terms: -16 + 16 = 0
0 + u2 = 0 + 16
u2 = 0 + 16

Combine like terms: 0 + 16 = 16
u2 = 16

Simplifying
u2 = 16

Take the square root of each side:
u = {-4, 4}