The equations are

 Since the coefficients of the y-terms,+1 and -1,are additive inverses,

you can eliminate these terms by adding the equations. .

add the equations to eliminate variable y.

         (Write the equations in column form and add)

                           (Divide each side by 5)

                                (Cancel common terms)

                                     (Divide: )

Now Substitute for x  in either equation to find the value of y.

   (Equation 1)

                              (Multiply:  )                           

            (Add 27 to each side)

            (Commutative property:  a+b=b+a)

                           (Additive inverse property: )

                                 (Additive indentity property: )

                                        (Add:  )

The solution is .

The solution is .