(u-7)(u+6)=0

Solution for (u-7)(u+6)=0 equation:

Simplifying
(u + -7)(u + 6) = 0

Reorder the terms:
(-7 + u)(u + 6) = 0

Reorder the terms:
(-7 + u)(6 + u) = 0

Multiply (-7 + u) * (6 + u)
(-7(6 + u) + u(6 + u)) = 0
((6 * -7 + u * -7) + u(6 + u)) = 0
((-42 + -7u) + u(6 + u)) = 0
(-42 + -7u + (6 * u + u * u)) = 0
(-42 + -7u + (6u + u2)) = 0

Combine like terms: -7u + 6u = -1u
(-42 + -1u + u2) = 0

Solving
-42 + -1u + u2 = 0

Solving for variable 'u'.

Factor a trinomial.
(-6 + -1u)(7 + -1u) = 0

Subproblem 1
Set the factor '(-6 + -1u)' equal to zero and attempt to solve:

Simplifying
-6 + -1u = 0

Solving
-6 + -1u = 0

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

Add '6' to each side of the equation.
-6 + 6 + -1u = 0 + 6

Combine like terms: -6 + 6 = 0
0 + -1u = 0 + 6
-1u = 0 + 6

Combine like terms: 0 + 6 = 6
-1u = 6

Divide each side by '-1'.
u = -6

Simplifying
u = -6
Subproblem 2
Set the factor '(7 + -1u)' equal to zero and attempt to solve:

Simplifying
7 + -1u = 0

Solving
7 + -1u = 0

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

Add '-7' to each side of the equation.
7 + -7 + -1u = 0 + -7

Combine like terms: 7 + -7 = 0
0 + -1u = 0 + -7
-1u = 0 + -7

Combine like terms: 0 + -7 = -7
-1u = -7

Divide each side by '-1'.
u = 7

Simplifying
u = 7
Solution
u = {-6, 7}