Question

sole by elimination
9x+6y=-30
4x-4y=20

Answer 1

representing 9x+6y=-30 as equation one and 4x-4y=20 by equation two.
multiply equation one by 2 and equation two by 3.
you will get 18x+12y=-60 and 12x-12y=-60
adding the two new equations, 6x=0
therefore x=0.
subtituting x=0 into equation one or two and solving it gives y=-5

Answer 2

oh ok thx