2x - y = 2
x + 2y = -9
Multiply the first equation by 2:
2*[2x - y = 2]
4x - 2y = 4
Now add this to the second equation to eliminate the y's and solve for x:
4x - 2y = 4
x + 2y = -9
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5x + 0 = -5
x = -1
Solve for y:
2x - y = 2
2(-1) - y = 2
-2 - y = 2
-y = 4
y = -4
Check:
2x - y = 2
2(-1) - (-4) = 2
-2 + 4 = 2
2 = 2 Check!
x + 2y = -9
(-1) + 2(-4) = -9
-1 + (-8) = -9
-9 = -9 Check!
To solve graphically, graph each line. They will intersect at the point (-1,-4). Click on the link below to see the graphical solution.
http://www.wyzant.com/resources/files/287951/intersection_of_two_lines
