5x^2-21x=-16

Solution for 5x^2-21x=-16 equation:

Simplifying
5x2 + -21x = -16

Reorder the terms:
-21x + 5x2 = -16

Solving
-21x + 5x2 = -16

Solving for variable 'x'.

Reorder the terms:
16 + -21x + 5x2 = -16 + 16

Combine like terms: -16 + 16 = 0
16 + -21x + 5x2 = 0

Factor a trinomial.
(1 + -1x)(16 + -5x) = 0

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

Simplifying
1 + -1x = 0

Solving
1 + -1x = 0

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

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

Combine like terms: 1 + -1 = 0
0 + -1x = 0 + -1
-1x = 0 + -1

Combine like terms: 0 + -1 = -1
-1x = -1

Divide each side by '-1'.
x = 1

Simplifying
x = 1
Subproblem 2
Set the factor '(16 + -5x)' equal to zero and attempt to solve:

Simplifying
16 + -5x = 0

Solving
16 + -5x = 0

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

Add '-16' to each side of the equation.
16 + -16 + -5x = 0 + -16

Combine like terms: 16 + -16 = 0
0 + -5x = 0 + -16
-5x = 0 + -16

Combine like terms: 0 + -16 = -16
-5x = -16

Divide each side by '-5'.
x = 3.2

Simplifying
x = 3.2
Solution
x = {1, 3.2}