typo
You can not find values for a , y and b from two equations.
Either y is b or b is y.
2a+12y=-7 3a+2b=7
2 answers
Assuming your equations are:
2a + 12b = -7
3a + 2b = 7
multiply the 2nd equation by 6 to get
18a + 12b = 42
then subtract the 1st, that will eliminate the b, and go from there
2a + 12b = -7
3a + 2b = 7
multiply the 2nd equation by 6 to get
18a + 12b = 42
then subtract the 1st, that will eliminate the b, and go from there