Simplifying
7.85 + -2.15c = 20.75
Solving
7.85 + -2.15c = 20.75
Solving for variable 'c'.
Move all terms containing c to the left, all other terms to the right.
Add '-7.85' to each side of the equation.
7.85 + -7.85 + -2.15c = 20.75 + -7.85
Combine like terms: 7.85 + -7.85 = 0.00
0.00 + -2.15c = 20.75 + -7.85
-2.15c = 20.75 + -7.85
Combine like terms: 20.75 + -7.85 = 12.9
-2.15c = 12.9
Divide each side by '-2.15'.
c = -6
Simplifying
c = -6