Solve the simultaneous equations for x and y: 2x+4y=-12 and y=-x-2
From the question we have y = -x - 2 so we can sub in -x-2 everywhere there is a y in the first equation.
The equation is then 2x+4(-x-2) = -12 expanding the brackets we get -2x-8=-12 which you can then rearrange to get x=2.
Finally we must remember to find the value for y as well, we can use the value for x we just found and sub it ino either equation.
Subbing into the 2nd equation we get y=-2-2 so y=-4
DG
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