Question

Which expression can you substitute in the indicated equation to solve the system of equations shown below?

4x + 3y = 4

3x + y = -2

Answer 1

The answer must be -3x-2 because when you bring y to the other side, y becomes negative. So it would be 3x= -2-y. Bring the 2 to the other side, it becomes positive. So.. 3x+2=-y. To get a positive y, we have to divide everything by -1. So it becomes -3x-2=y. Hope this helps