(U-3)(U+3)=0

Solution for (U-3)(U+3)=0 equation:

Simplifying
(U + -3)(U + 3) = 0

Reorder the terms:
(-3 + U)(U + 3) = 0

Reorder the terms:
(-3 + U)(3 + U) = 0

Multiply (-3 + U) * (3 + U)
(-3(3 + U) + U(3 + U)) = 0
((3 * -3 + U * -3) + U(3 + U)) = 0
((-9 + -3U) + U(3 + U)) = 0
(-9 + -3U + (3 * U + U * U)) = 0
(-9 + -3U + (3U + U2)) = 0

Combine like terms: -3U + 3U = 0
(-9 + 0 + U2) = 0
(-9 + U2) = 0

Solving
-9 + U2 = 0

Solving for variable 'U'.

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

Add '9' to each side of the equation.
-9 + 9 + U2 = 0 + 9

Combine like terms: -9 + 9 = 0
0 + U2 = 0 + 9
U2 = 0 + 9

Combine like terms: 0 + 9 = 9
U2 = 9

Simplifying
U2 = 9

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