-7k(k)+40k-57=0

Solution for -7k(k)+40k-57=0 equation:

Simplifying
-7k(k) + 40k + -57 = 0

Multiply k * k
-7k2 + 40k + -57 = 0

Reorder the terms:
-57 + 40k + -7k2 = 0

Solving
-57 + 40k + -7k2 = 0

Solving for variable 'k'.

Factor a trinomial.
(-3 + k)(19 + -7k) = 0

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

Simplifying
-3 + k = 0

Solving
-3 + k = 0

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

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

Combine like terms: -3 + 3 = 0
0 + k = 0 + 3
k = 0 + 3

Combine like terms: 0 + 3 = 3
k = 3

Simplifying
k = 3
Subproblem 2
Set the factor '(19 + -7k)' equal to zero and attempt to solve:

Simplifying
19 + -7k = 0

Solving
19 + -7k = 0

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

Add '-19' to each side of the equation.
19 + -19 + -7k = 0 + -19

Combine like terms: 19 + -19 = 0
0 + -7k = 0 + -19
-7k = 0 + -19

Combine like terms: 0 + -19 = -19
-7k = -19

Divide each side by '-7'.
k = 2.714285714

Simplifying
k = 2.714285714
Solution
k = {3, 2.714285714}