Solve for f
f=2\left(x+9\right)
Solve for x
x=\frac{f-18}{2}
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f-25=2x-7
Multiply 1 and 25 to get 25.
f=2x-7+25
Add 25 to both sides.
f=2x+18
Add -7 and 25 to get 18.
f-25=2x-7
Multiply 1 and 25 to get 25.
2x-7=f-25
Swap sides so that all variable terms are on the left hand side.
2x=f-25+7
Add 7 to both sides.
2x=f-18
Add -25 and 7 to get -18.
\frac{2x}{2}=\frac{f-18}{2}
Divide both sides by 2.
x=\frac{f-18}{2}
Dividing by 2 undoes the multiplication by 2.
x=\frac{f}{2}-9
Divide f-18 by 2.
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