2r^2+8r-3=-9

Solution for 2r^2+8r-3=-9 equation:

Simplifying
2r2 + 8r + -3 = -9

Reorder the terms:
-3 + 8r + 2r2 = -9

Solving
-3 + 8r + 2r2 = -9

Solving for variable 'r'.

Reorder the terms:
-3 + 9 + 8r + 2r2 = -9 + 9

Combine like terms: -3 + 9 = 6
6 + 8r + 2r2 = -9 + 9

Combine like terms: -9 + 9 = 0
6 + 8r + 2r2 = 0

Factor out the Greatest Common Factor (GCF), '2'.
2(3 + 4r + r2) = 0

Factor a trinomial.
2((3 + r)(1 + r)) = 0

Ignore the factor 2.
Subproblem 1
Set the factor '(3 + r)' equal to zero and attempt to solve:

Simplifying
3 + r = 0

Solving
3 + r = 0

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

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

Combine like terms: 3 + -3 = 0
0 + r = 0 + -3
r = 0 + -3

Combine like terms: 0 + -3 = -3
r = -3

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

Simplifying
1 + r = 0

Solving
1 + r = 0

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

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

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

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

Simplifying
r = -1
Solution
r = {-3, -1}