20y^2+31y-9=0

Solution for 20y^2+31y-9=0 equation:

Simplifying
20y2 + 31y + -9 = 0

Reorder the terms:
-9 + 31y + 20y2 = 0

Solving
-9 + 31y + 20y2 = 0

Solving for variable 'y'.

Factor a trinomial.
(-9 + -5y)(1 + -4y) = 0

Subproblem 1
Set the factor '(-9 + -5y)' equal to zero and attempt to solve:

Simplifying
-9 + -5y = 0

Solving
-9 + -5y = 0

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

Add '9' to each side of the equation.
-9 + 9 + -5y = 0 + 9

Combine like terms: -9 + 9 = 0
0 + -5y = 0 + 9
-5y = 0 + 9

Combine like terms: 0 + 9 = 9
-5y = 9

Divide each side by '-5'.
y = -1.8

Simplifying
y = -1.8
Subproblem 2
Set the factor '(1 + -4y)' equal to zero and attempt to solve:

Simplifying
1 + -4y = 0

Solving
1 + -4y = 0

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

Add '-1' to each side of the equation.
1 + -1 + -4y = 0 + -1

Combine like terms: 1 + -1 = 0
0 + -4y = 0 + -1
-4y = 0 + -1

Combine like terms: 0 + -1 = -1
-4y = -1

Divide each side by '-4'.
y = 0.25

Simplifying
y = 0.25
Solution
y = {-1.8, 0.25}