m^2+2m-18=0

Solution for m^2+2m-18=0 equation:

Simplifying
m2 + 2m + -18 = 0

Reorder the terms:
-18 + 2m + m2 = 0

Solving
-18 + 2m + m2 = 0

Solving for variable 'm'.

Begin completing the square.

Move the constant term to the right:

Add '18' to each side of the equation.
-18 + 2m + 18 + m2 = 0 + 18

Reorder the terms:
-18 + 18 + 2m + m2 = 0 + 18

Combine like terms: -18 + 18 = 0
0 + 2m + m2 = 0 + 18
2m + m2 = 0 + 18

Combine like terms: 0 + 18 = 18
2m + m2 = 18

The m term is 2m.  Take half its coefficient (1).
Square it (1) and add it to both sides.

Add '1' to each side of the equation.
2m + 1 + m2 = 18 + 1

Reorder the terms:
1 + 2m + m2 = 18 + 1

Combine like terms: 18 + 1 = 19
1 + 2m + m2 = 19

Factor a perfect square on the left side:
(m + 1)(m + 1) = 19

Calculate the square root of the right side: 4.358898944

Break this problem into two subproblems by setting 
(m + 1) equal to 4.358898944 and -4.358898944.

Subproblem 1
m + 1 = 4.358898944

Simplifying
m + 1 = 4.358898944

Reorder the terms:
1 + m = 4.358898944

Solving
1 + m = 4.358898944

Solving for variable 'm'.

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

Add '-1' to each side of the equation.
1 + -1 + m = 4.358898944 + -1

Combine like terms: 1 + -1 = 0
0 + m = 4.358898944 + -1
m = 4.358898944 + -1

Combine like terms: 4.358898944 + -1 = 3.358898944
m = 3.358898944

Simplifying
m = 3.358898944

Subproblem 2
m + 1 = -4.358898944

Simplifying
m + 1 = -4.358898944

Reorder the terms:
1 + m = -4.358898944

Solving
1 + m = -4.358898944

Solving for variable 'm'.

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

Add '-1' to each side of the equation.
1 + -1 + m = -4.358898944 + -1

Combine like terms: 1 + -1 = 0
0 + m = -4.358898944 + -1
m = -4.358898944 + -1

Combine like terms: -4.358898944 + -1 = -5.358898944
m = -5.358898944

Simplifying
m = -5.358898944

Solution
The solution to the problem is based on the solutions
from the subproblems.
m = {3.358898944, -5.358898944}