Solve for x
x=-\frac{A}{3}-7
Solve for A
A=-3x-21
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A=-3x-21
Use the distributive property to multiply -3 by x+7.
-3x-21=A
Swap sides so that all variable terms are on the left hand side.
-3x=A+21
Add 21 to both sides.
\frac{-3x}{-3}=\frac{A+21}{-3}
Divide both sides by -3.
x=\frac{A+21}{-3}
Dividing by -3 undoes the multiplication by -3.
x=-\frac{A}{3}-7
Divide A+21 by -3.
A=-3x-21
Use the distributive property to multiply -3 by x+7.
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