yep.
x=-4 and y=-8.
This is how it starts:
3x+y=-20
Since y is 2x, just replace the y with 2x. Now you have this:
3x+2x=-20
Combine the two x numbers and you get this:
5x=-20
Divide 5 by 5 and -20 by 5. Now you get this:
x=-4
That's the answer for x but now you need Y.
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y=2x
Replace the x with -4
y=2(-4)
You multiply them and you get this answer:
y=-8
Here's what the final answer should look like:
{( -4,-8 )}