Use the elimination method to solve the following systems of equations

Question

5x+ 8y= 25

3x−15 =y

Answer 1

The system of equations are

5x + 8y  =  25 ------------> (1)

3x − 15  =  y --------------> (2)

Rewrite the equation (2)

3x - y  =  15 -------------> (3)

Multiply Eq(3) with 8 and add to Eq (1)

Eq (3) X 8 ======>  24x - 8y  =  120

Eq (1) =========>    5x + 8y  =  25

                             ------------------------------

                                    29x  =  145

                                        x  =  145/29

                                        x  =  5

Substitute x = 5 in Eq (2)

3(5) − 15  =  y

15 − 15  =  y

y  =  0

The solutions are x = 5  and  y = 0.