Question

PLEASE EXPLAIN WHAT IT MEANS TO "ADD THEM TOGETHER" I have seen people do this in other explanations but i don't get it..

Solve the following system of equations graphically.

x + y - 4 = 0

x - y = 0



The solution lies in quadrant _____.

III
II
I
IV

Answer 1

quadrant I

Explanation:

x + y - 4 = 0 becomes x + y = 4, so we have the equations x + y = 4 and x - y = 0. Add these two equations to eliminate y, obtaining 2x = 4. From this, x = 2, and so y = 2. So the solution is in quadrant I.