You have to solve for 1 variable I'm pretty sure they want 4y and not just y becaseu taht is too easy
-6x+4y=33 5x+18y=29
solve for 1 variable
may be messy -6x+4y=33 add 6x both sides 4y=33+6x divide both sides by 4 y=(33+6x)/4 sub that for y in other equation
5x+18((33+6x)/4)=29 5x+9(33+6x)/2=29 5x+(297+54x)/2=29 (10x/2)+(297+54x)/2=29 times both sides by 2 10x+297+54x=58 297+64x=58 minus 297 both sides 64x=-239 divide both sides by 64 x=-239/64 sub back