Solve for k
k=20\left(x-4\right)
Solve for x
x=\frac{k+80}{20}
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-k=80-x\times 20
Subtract x\times 20 from both sides.
-k=80-20x
Multiply -1 and 20 to get -20.
\frac{-k}{-1}=\frac{80-20x}{-1}
Divide both sides by -1.
k=\frac{80-20x}{-1}
Dividing by -1 undoes the multiplication by -1.
k=20x-80
Divide 80-20x by -1.
x\times 20=80+k
Add k to both sides.
20x=k+80
The equation is in standard form.
\frac{20x}{20}=\frac{k+80}{20}
Divide both sides by 20.
x=\frac{k+80}{20}
Dividing by 20 undoes the multiplication by 20.
x=\frac{k}{20}+4
Divide 80+k by 20.
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