f) 2x+9y=-9 -3x+3y=8 g) 2x+3y=4 8x-5y=-1 h) x-y=0 x+y+z=4 x+2y+3z=9
f) 2x+9y=-9
-3x+3y=8
g) 2x+3y=4
8x-5y=-1
h) x-y=0
x+y+z=4
x+2y+3z=9
2x+9y=-9 -3x+3y=8 2x=-9-9y/:2 -3x+3y=8 x=4½-4½y -3(4½-4½y)+3y=8 x=4½-4½y -13,5+13,5y+3y=8 x=4½-4½y 16,5y=21,5 /:16,5