400-40Q-3Q^2=0

Solution for 400-40Q-3Q^2=0 equation:

Simplifying
400 + -40Q + -3Q2 = 0

Solving
400 + -40Q + -3Q2 = 0

Solving for variable 'Q'.

Factor a trinomial.
(20 + -3Q)(20 + Q) = 0

Subproblem 1
Set the factor '(20 + -3Q)' equal to zero and attempt to solve:

Simplifying
20 + -3Q = 0

Solving
20 + -3Q = 0

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

Add '-20' to each side of the equation.
20 + -20 + -3Q = 0 + -20

Combine like terms: 20 + -20 = 0
0 + -3Q = 0 + -20
-3Q = 0 + -20

Combine like terms: 0 + -20 = -20
-3Q = -20

Divide each side by '-3'.
Q = 6.666666667

Simplifying
Q = 6.666666667
Subproblem 2
Set the factor '(20 + Q)' equal to zero and attempt to solve:

Simplifying
20 + Q = 0

Solving
20 + Q = 0

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

Add '-20' to each side of the equation.
20 + -20 + Q = 0 + -20

Combine like terms: 20 + -20 = 0
0 + Q = 0 + -20
Q = 0 + -20

Combine like terms: 0 + -20 = -20
Q = -20

Simplifying
Q = -20
Solution
Q = {6.666666667, -20}