Solve for r
r = \frac{125}{8} = 15\frac{5}{8} = 15.625
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8\left(r-10\right)=5\times 9
Variable r cannot be equal to 10 since division by zero is not defined. Multiply both sides of the equation by 5\left(r-10\right), the least common multiple of 5,r-10.
8r-80=5\times 9
Use the distributive property to multiply 8 by r-10.
8r-80=45
Multiply 5 and 9 to get 45.
8r=45+80
Add 80 to both sides.
8r=125
Add 45 and 80 to get 125.
r=\frac{125}{8}
Divide both sides by 8.
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