y=x-7
2x+y=8
3 answers
2x+(x-7)=8 you have to substite the equation for y into the problem
It does not really matter so long as what used to read as having two variable letters gets knocked down to one variable letter. You can either describe x in terms of y or y in terms of x. Plug and chug, then solve with algebraic maneuvers.
6x + 3y = -6
2x + y = -2
2x + y = -2