Question

{-2x+y=6
{ 3x-2y=-9

Answer 1

{-2x+y=6/*2
{ 3x-2y=-9

-4x+2y=12

3x-2y=-9

-4x+2y+3x-2y=3

-x=3/:(-1)
x=-3

 

3x-2y=-9

3*(-3)-2y=-9

-9-2y=-9

-2y=0/:(-2)

y=0

Answer 2

{-2x+y=6/•2

{3x-2y=-9

{-4x+2y=12

{3x-2y=-9

_________

{-x=3/x-1

{x=-3

{-2x+y=6

{-2•-3+y=6

{6+y=6

{y=6-6

{y=0