7a^2+15a=-8

Solution for 7a^2+15a=-8 equation:

Simplifying
7a2 + 15a = -8

Reorder the terms:
15a + 7a2 = -8

Solving
15a + 7a2 = -8

Solving for variable 'a'.

Reorder the terms:
8 + 15a + 7a2 = -8 + 8

Combine like terms: -8 + 8 = 0
8 + 15a + 7a2 = 0

Factor a trinomial.
(8 + 7a)(1 + a) = 0

Subproblem 1
Set the factor '(8 + 7a)' equal to zero and attempt to solve:

Simplifying
8 + 7a = 0

Solving
8 + 7a = 0

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

Add '-8' to each side of the equation.
8 + -8 + 7a = 0 + -8

Combine like terms: 8 + -8 = 0
0 + 7a = 0 + -8
7a = 0 + -8

Combine like terms: 0 + -8 = -8
7a = -8

Divide each side by '7'.
a = -1.142857143

Simplifying
a = -1.142857143
Subproblem 2
Set the factor '(1 + a)' equal to zero and attempt to solve:

Simplifying
1 + a = 0

Solving
1 + a = 0

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

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

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

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

Simplifying
a = -1
Solution
a = {-1.142857143, -1}