cancel something
we cancel x's
multiply 1st equation by 5 and 2nd by 7 and add them
-35x-30y=-5
35x-28y=7 +
0x-58y=2
-58y=2
divide both sides by -58
y=-1/29
sub back
5x-4(-1/29)=1
5x+4/29=1
minus 4/29 from both sides
note, 1=29/29
5x=25/29
divide bot sides by 5 (or times 1/5)
x=5/29
(5/29,-1/29)
