Answer :

To get the answer we have to tranform into y=ax+b form
-2x+4y=68          /+2x
4y=2x+68          /:4
y=[tex] \frac{1}{2} x+17[/tex]  - its the result

13x+4y=284           /-13x
4y=-13x+284        /:4
y=[tex]- \frac{13}{4}+ 71[/tex]
y=-[tex]3 \frac{1}{4}x+71 [/tex] - its the result