Solve for r
r=19
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2\left(r+9\right)=7\times 8
Multiply both sides of the equation by 14, the least common multiple of 7,2.
2r+18=7\times 8
Use the distributive property to multiply 2 by r+9.
2r+18=56
Multiply 7 and 8 to get 56.
2r=56-18
Subtract 18 from both sides.
2r=38
Subtract 18 from 56 to get 38.
r=\frac{38}{2}
Divide both sides by 2.
r=19
Divide 38 by 2 to get 19.
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