[x^2+3x-15]=3

Solution for [x^2+3x-15]=3 equation:

Simplifying
[x2 + 3x + -15] = 3

Reorder the terms:
[-15 + 3x + x2] = 3

Remove brackets around [-15 + 3x + x2]
-15 + 3x + x2 = 3

Solving
-15 + 3x + x2 = 3

Solving for variable 'x'.

Reorder the terms:
-15 + -3 + 3x + x2 = 3 + -3

Combine like terms: -15 + -3 = -18
-18 + 3x + x2 = 3 + -3

Combine like terms: 3 + -3 = 0
-18 + 3x + x2 = 0

Factor a trinomial.
(-6 + -1x)(3 + -1x) = 0

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

Simplifying
-6 + -1x = 0

Solving
-6 + -1x = 0

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

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

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

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

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

Simplifying
x = -6
Subproblem 2
Set the factor '(3 + -1x)' equal to zero and attempt to solve:

Simplifying
3 + -1x = 0

Solving
3 + -1x = 0

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

Add '-3' to each side of the equation.
3 + -3 + -1x = 0 + -3

Combine like terms: 3 + -3 = 0
0 + -1x = 0 + -3
-1x = 0 + -3

Combine like terms: 0 + -3 = -3
-1x = -3

Divide each side by '-1'.
x = 3

Simplifying
x = 3
Solution
x = {-6, 3}