Since cc is on the right side of the equation, switch the sides so it is on the left side of the equation.6(2c−12)−4c=8(c−9)6(2c-12)-4c=8(c-9)Simplify the left side.8c−72=8(c−9)8c-72=8(c-9)Simplify the right side.8c−72=8c−728c-72=8c-72Move all terms containing cc to the left side of the equation..−72=−72-72=-72Since −72=−72-72=-72, the equation will always be true.Always true