You can put this solution on YOUR website! Solve the linear equations by graphing.
2x+y=0
3x+y=-1
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They're 2 straight lines.
You need 2 points to graph them.
2x+y=0
y = -2x
Pick 2 values for x and find y
Plot the points
Draw a line thru them.
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Do the same for the other eqn
The intersection is the solution of the system.