Solve for r
r=\frac{x}{2}-\frac{15}{4}
Solve for x
x=2r+\frac{15}{2}
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4r+10=2x-5
Swap sides so that all variable terms are on the left hand side.
4r=2x-5-10
Subtract 10 from both sides.
4r=2x-15
Subtract 10 from -5 to get -15.
\frac{4r}{4}=\frac{2x-15}{4}
Divide both sides by 4.
r=\frac{2x-15}{4}
Dividing by 4 undoes the multiplication by 4.
r=\frac{x}{2}-\frac{15}{4}
Divide 2x-15 by 4.
2x=4r+10+5
Add 5 to both sides.
2x=4r+15
Add 10 and 5 to get 15.
\frac{2x}{2}=\frac{4r+15}{2}
Divide both sides by 2.
x=\frac{4r+15}{2}
Dividing by 2 undoes the multiplication by 2.
x=2r+\frac{15}{2}
Divide 4r+15 by 2.
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