5a^2=-13-8a

Solution for 5a^2=-13-8a equation:

Simplifying
5a2 = -13 + -8a

Solving
5a2 = -13 + -8a

Solving for variable 'a'.

Reorder the terms:
13 + 8a + 5a2 = -13 + -8a + 13 + 8a

Reorder the terms:
13 + 8a + 5a2 = -13 + 13 + -8a + 8a

Combine like terms: -13 + 13 = 0
13 + 8a + 5a2 = 0 + -8a + 8a
13 + 8a + 5a2 = -8a + 8a

Combine like terms: -8a + 8a = 0
13 + 8a + 5a2 = 0

Begin completing the square.  Divide all terms by
5 the coefficient of the squared term: 

Divide each side by '5'.
2.6 + 1.6a + a2 = 0

Move the constant term to the right:

Add '-2.6' to each side of the equation.
2.6 + 1.6a + -2.6 + a2 = 0 + -2.6

Reorder the terms:
2.6 + -2.6 + 1.6a + a2 = 0 + -2.6

Combine like terms: 2.6 + -2.6 = 0.0
0.0 + 1.6a + a2 = 0 + -2.6
1.6a + a2 = 0 + -2.6

Combine like terms: 0 + -2.6 = -2.6
1.6a + a2 = -2.6

The a term is 1.6a.  Take half its coefficient (0.8).
Square it (0.64) and add it to both sides.

Add '0.64' to each side of the equation.
1.6a + 0.64 + a2 = -2.6 + 0.64

Reorder the terms:
0.64 + 1.6a + a2 = -2.6 + 0.64

Combine like terms: -2.6 + 0.64 = -1.96
0.64 + 1.6a + a2 = -1.96

Factor a perfect square on the left side:
(a + 0.8)(a + 0.8) = -1.96

Can't calculate square root of the right side.

The solution to this equation could not be determined.