r^2+r-156=

Solution for r^2+r-156= equation:

Simplifying
r2 + r + -156 = 0

Reorder the terms:
-156 + r + r2 = 0

Solving
-156 + r + r2 = 0

Solving for variable 'r'.

Factor a trinomial.
(-13 + -1r)(12 + -1r) = 0

Subproblem 1
Set the factor '(-13 + -1r)' equal to zero and attempt to solve:

Simplifying
-13 + -1r = 0

Solving
-13 + -1r = 0

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

Add '13' to each side of the equation.
-13 + 13 + -1r = 0 + 13

Combine like terms: -13 + 13 = 0
0 + -1r = 0 + 13
-1r = 0 + 13

Combine like terms: 0 + 13 = 13
-1r = 13

Divide each side by '-1'.
r = -13

Simplifying
r = -13
Subproblem 2
Set the factor '(12 + -1r)' equal to zero and attempt to solve:

Simplifying
12 + -1r = 0

Solving
12 + -1r = 0

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

Add '-12' to each side of the equation.
12 + -12 + -1r = 0 + -12

Combine like terms: 12 + -12 = 0
0 + -1r = 0 + -12
-1r = 0 + -12

Combine like terms: 0 + -12 = -12
-1r = -12

Divide each side by '-1'.
r = 12

Simplifying
r = 12
Solution
r = {-13, 12}