First, we are going to want to plug in the values we are given. In this case, we will end up with the equation:

From here, we can solve the equation to find
:

- Apply the commutative property to rearrange the terms on the right-side of the equation to make the distributive property more apparent

- Apply the distributive property

- Subtract 8 from both sides of the equation

- Divide both sides of the equation by -2
We have found that c = 1.