2b^2-20b-78=

Solution for 2b^2-20b-78= equation:

Simplifying
2b2 + -20b + -78 = 0

Reorder the terms:
-78 + -20b + 2b2 = 0

Solving
-78 + -20b + 2b2 = 0

Solving for variable 'b'.

Factor out the Greatest Common Factor (GCF), '2'.
2(-39 + -10b + b2) = 0

Factor a trinomial.
2((-3 + -1b)(13 + -1b)) = 0

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

Simplifying
-3 + -1b = 0

Solving
-3 + -1b = 0

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

Add '3' to each side of the equation.
-3 + 3 + -1b = 0 + 3

Combine like terms: -3 + 3 = 0
0 + -1b = 0 + 3
-1b = 0 + 3

Combine like terms: 0 + 3 = 3
-1b = 3

Divide each side by '-1'.
b = -3

Simplifying
b = -3
Subproblem 2
Set the factor '(13 + -1b)' equal to zero and attempt to solve:

Simplifying
13 + -1b = 0

Solving
13 + -1b = 0

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

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

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

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

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

Simplifying
b = 13
Solution
b = {-3, 13}