The equations are

Rewrite the second equation

            (Subtract 5y from each side)

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

                       (Additive inverse property: )

                         (Additive indentity property: ) \ \

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

you can eliminate these terms by adding the equations. .

add the equations to eliminate variable x.

                  (Write the equations in column form and add)

                         (Divide each side by 4)

                                   (Cancel common terms)

                                        (Divide:  )

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

   (Equation 1)                         

               (Add 12 to each side) \ \

                    (Additive inverse property: )

                          (Additive indentity property: )

                                (Add:  )

                   (Multiply each side by negative one)

                             (Product of two same signs is positive)

                                (Product of two diffirent signs is negative)

The solution is .

The solution is .