Solve for r
r=x+7
Solve for x
x=r-7
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-r=-7-x
Subtract x from both sides.
-r=-x-7
The equation is in standard form.
\frac{-r}{-1}=\frac{-x-7}{-1}
Divide both sides by -1.
r=\frac{-x-7}{-1}
Dividing by -1 undoes the multiplication by -1.
r=x+7
Divide -7-x by -1.
x=-7+r
Add r to both sides.
Examples
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Matrix
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Integration
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Limits
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