120=x(x+7)

Solution for 120=x(x+7) equation:

Simplifying
120 = x(x + 7)

Reorder the terms:
120 = x(7 + x)
120 = (7 * x + x * x)
120 = (7x + x2)

Solving
120 = 7x + x2

Solving for variable 'x'.

Reorder the terms:
120 + -7x + -1x2 = 7x + -7x + x2 + -1x2

Combine like terms: 7x + -7x = 0
120 + -7x + -1x2 = 0 + x2 + -1x2
120 + -7x + -1x2 = x2 + -1x2

Combine like terms: x2 + -1x2 = 0
120 + -7x + -1x2 = 0

Factor a trinomial.
(8 + -1x)(15 + x) = 0

Subproblem 1
Set the factor '(8 + -1x)' equal to zero and attempt to solve:

Simplifying
8 + -1x = 0

Solving
8 + -1x = 0

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

Add '-8' to each side of the equation.
8 + -8 + -1x = 0 + -8

Combine like terms: 8 + -8 = 0
0 + -1x = 0 + -8
-1x = 0 + -8

Combine like terms: 0 + -8 = -8
-1x = -8

Divide each side by '-1'.
x = 8

Simplifying
x = 8
Subproblem 2
Set the factor '(15 + x)' equal to zero and attempt to solve:

Simplifying
15 + x = 0

Solving
15 + x = 0

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

Add '-15' to each side of the equation.
15 + -15 + x = 0 + -15

Combine like terms: 15 + -15 = 0
0 + x = 0 + -15
x = 0 + -15

Combine like terms: 0 + -15 = -15
x = -15

Simplifying
x = -15
Solution
x = {8, -15}