Solve for k
k=-\frac{x}{2}
Solve for x
x=-2k
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2k=x-2x
Subtract 2x from both sides.
2k=-x
Combine x and -2x to get -x.
\frac{2k}{2}=-\frac{x}{2}
Divide both sides by 2.
k=-\frac{x}{2}
Dividing by 2 undoes the multiplication by 2.
2x+2k-x=0
Subtract x from both sides.
x+2k=0
Combine 2x and -x to get x.
x=-2k
Subtract 2k from both sides. Anything subtracted from zero gives its negation.
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