-21=c-6

Solution for -21=c-6 equation:

Simplifying
-21 = c + -6

Reorder the terms:
-21 = -6 + c

Solving
-21 = -6 + c

Solving for variable 'c'.

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

Add '-1c' to each side of the equation.
-21 + -1c = -6 + c + -1c

Combine like terms: c + -1c = 0
-21 + -1c = -6 + 0
-21 + -1c = -6

Add '21' to each side of the equation.
-21 + 21 + -1c = -6 + 21

Combine like terms: -21 + 21 = 0
0 + -1c = -6 + 21
-1c = -6 + 21

Combine like terms: -6 + 21 = 15
-1c = 15

Divide each side by '-1'.
c = -15

Simplifying
c = -15