L^2-40L+300=0

Solution for L^2-40L+300=0 equation:

Simplifying
L2 + -40L + 300 = 0

Reorder the terms:
300 + -40L + L2 = 0

Solving
300 + -40L + L2 = 0

Solving for variable 'L'.

Factor a trinomial.
(10 + -1L)(30 + -1L) = 0

Subproblem 1
Set the factor '(10 + -1L)' equal to zero and attempt to solve:

Simplifying
10 + -1L = 0

Solving
10 + -1L = 0

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

Add '-10' to each side of the equation.
10 + -10 + -1L = 0 + -10

Combine like terms: 10 + -10 = 0
0 + -1L = 0 + -10
-1L = 0 + -10

Combine like terms: 0 + -10 = -10
-1L = -10

Divide each side by '-1'.
L = 10

Simplifying
L = 10
Subproblem 2
Set the factor '(30 + -1L)' equal to zero and attempt to solve:

Simplifying
30 + -1L = 0

Solving
30 + -1L = 0

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

Add '-30' to each side of the equation.
30 + -30 + -1L = 0 + -30

Combine like terms: 30 + -30 = 0
0 + -1L = 0 + -30
-1L = 0 + -30

Combine like terms: 0 + -30 = -30
-1L = -30

Divide each side by '-1'.
L = 30

Simplifying
L = 30
Solution
L = {10, 30}