The equations are

Rewrite the second equation

                           (Add 2x to each side)

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

          (Additive inverse property: ) 

                        (Additive indentity property: )

 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 4)

                                  (Cancel common terms)

                                      (Divide:  )

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

   (Equation 1)

                           (Multiply:  )                           

           (Add 12 to each side)

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

                        (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 .