The equations are

             Equation (1)

           Equation (2)

Multiply equation (1) by 3. \ \

             Equation (3)

Subtract the equation (3) and equation (2) to eliminate the m variable.

          (Subtract the corresponding columns)

Apply division property of equality: if a = b, then.

Divide each side by 2.

Substitute  in equation (3).

Apply addition property of equality: If a = b then a b = b a.

Subtract 21.6 from each side.

\ \

Apply division property of equality: if a = b, then.

Divide each side by 1.2.

The solution is .

The solution is .