Answer: 2x+3y and 3x-9y
1) lets substitute 9, 4, and 1/3 into all the equations
2(4)+3(1/3)=9
8+1=9
9=9- this equation is true
(4)/2-3(1/3)
2-1=9
1=9- NOT TRUE
3(4)-9(1/3)=9
12-3=9
9=9-TRUE
4^2+6(1/3)
16+2=9
18=9 -NOT TRUE
(1/3)^2-21(4)
1/9-84=9
-83.88=9- NOTTRUE
