Question

1) {x/10-y/5=0,
{5x/3+y/6-7=0;
2) {x/4+y/8-2=0,
{2x/9+y/6-1=0;
3) {6x/7+5y/21-5=0
{9x/4-y/12-11=0;
4) {7x/3-y/9-4=0,
{8x/5-y/30-3=0
​