5*(c - 4) - x*(4 - c)
5*(c - 1*4) - x*(4 - c)
1*(c - 4)*(x + 5)
(1*(c - 4))*(x + 5)
-20 + 5*c + x*(-4 + c)
-20 + 5*c + x*(-4 + c)
-20 - 4*x + 5*c + c*x
-20 + 5*c - x*(4 - c)
-20 + 5*c - x*(4 - c)
-20 + 5*c + x*(-4 + c)
-20 + 5*c - x*(4 - c)
-20 + 5*c - x*(4 - c)
-20 + 5*c - x*(4 - c)
-20 + 5*c - x*(4 - c)