$y=\frac{15y-2}{7}$

$y=\frac{15y+2}{7}$

$y=15y-2$

$y=15y+2$

(2, 3)

(3, 2)

(2, 2)

(3, 3)

 $3s+2t=6$  

 $3s+2t=36$  

 $2s+3t=6$  

 $2s+3t=36$  

(5, 3)

(3, 5)

(5, 5)

(3, 3)