Solve for r
r=1
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2r-\frac{1}{2}\times 5-\frac{1}{2}\left(-1\right)r=0
Use the distributive property to multiply -\frac{1}{2} by 5-r.
2r+\frac{-5}{2}-\frac{1}{2}\left(-1\right)r=0
Express -\frac{1}{2}\times 5 as a single fraction.
2r-\frac{5}{2}-\frac{1}{2}\left(-1\right)r=0
Fraction \frac{-5}{2} can be rewritten as -\frac{5}{2} by extracting the negative sign.
2r-\frac{5}{2}+\frac{1}{2}r=0
Multiply -\frac{1}{2} and -1 to get \frac{1}{2}.
\frac{5}{2}r-\frac{5}{2}=0
Combine 2r and \frac{1}{2}r to get \frac{5}{2}r.
\frac{5}{2}r=\frac{5}{2}
Add \frac{5}{2} to both sides. Anything plus zero gives itself.
r=\frac{5}{2}\times \frac{2}{5}
Multiply both sides by \frac{2}{5}, the reciprocal of \frac{5}{2}.
r=1
Cancel out \frac{5}{2} and its reciprocal \frac{2}{5}.
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