Verified Answer :

  1. we can add them to eliminate y's

    3x-4y=-16
    -x+4y=24 +
    2x+0y=8

    2x=8
    divide by 2
    x=4

    sub back
    -x+4y=24
    -4+4y=24
    add 4 both sides
    4y=28
    divide by 4
    y=7

    (x,y)
    (4,7)




    3.
    add them to eliminate y's

    -5x+3y=12
    -2x-3y=-33 +
    -7x+0y=-21

    -7x=-21
    divide both sides by -7
    x=3

    sub back
    -2x-3y=-33
    -6-3y=-33
    add 6 to both sides
    -3y=-27
    divide both sides by -3
    y=9

    (x,y)
    (3,9)




    1. (4,7)
    3. (3,9)