You can put this solution on YOUR website!
you know that y=2x, so replace y in the longer equation with 2x:
This can be simplified:
x^2 + 2(4x^2) = 18
x^2 + 8x^2 = 18
Now divide both side by 9:
So x=3 or x=-3
Recalling that y=2x;
y=6 or y=-6
This can be written in the form of coordinates on a graph, like this:
"The solutions are (3,6) and (-3,-6)"
I hope this helps.
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