Find the EXACT values of the x-coordinates of the points of intersection of the graphs of the given equations.

{y^2 - 2x^2=3}

{x+y=3}

? (lesser x-value)

? (greater x-value)

I thought the goal was to cancel either x or y out. Then, the value would be used to plug in and solve for the other variable. I have looked at the one example that my instructor provided and did not help. I need a real explanation for how to approach and solve this problem.