Solve for b
b=\frac{9\left(r-16\right)}{8}
r\neq 8
Solve for r
r=\frac{8\left(b+18\right)}{9}
b\neq -9
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\left(r-8\right)\times 9=\left(b+9\right)\times 8
Variable b cannot be equal to -9 since division by zero is not defined. Multiply both sides of the equation by \left(r-8\right)\left(b+9\right), the least common multiple of b+9,r-8.
9r-72=\left(b+9\right)\times 8
Use the distributive property to multiply r-8 by 9.
9r-72=8b+72
Use the distributive property to multiply b+9 by 8.
8b+72=9r-72
Swap sides so that all variable terms are on the left hand side.
8b=9r-72-72
Subtract 72 from both sides.
8b=9r-144
Subtract 72 from -72 to get -144.
\frac{8b}{8}=\frac{9r-144}{8}
Divide both sides by 8.
b=\frac{9r-144}{8}
Dividing by 8 undoes the multiplication by 8.
b=\frac{9r}{8}-18
Divide -144+9r by 8.
b=\frac{9r}{8}-18\text{, }b\neq -9
Variable b cannot be equal to -9.
\left(r-8\right)\times 9=\left(b+9\right)\times 8
Variable r cannot be equal to 8 since division by zero is not defined. Multiply both sides of the equation by \left(r-8\right)\left(b+9\right), the least common multiple of b+9,r-8.
9r-72=\left(b+9\right)\times 8
Use the distributive property to multiply r-8 by 9.
9r-72=8b+72
Use the distributive property to multiply b+9 by 8.
9r=8b+72+72
Add 72 to both sides.
9r=8b+144
Add 72 and 72 to get 144.
\frac{9r}{9}=\frac{8b+144}{9}
Divide both sides by 9.
r=\frac{8b+144}{9}
Dividing by 9 undoes the multiplication by 9.
r=\frac{8b}{9}+16
Divide 144+8b by 9.
r=\frac{8b}{9}+16\text{, }r\neq 8
Variable r cannot be equal to 8.
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