Solve for r
r=7
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3r-3+\left(r-1\right)\times 4=\left(r+7\right)\times 3
Variable r cannot be equal to any of the values -7,1 since division by zero is not defined. Multiply both sides of the equation by \left(r-1\right)\left(r+7\right), the least common multiple of r^{2}+6r-7,r+7,r-1.
3r-3+4r-4=\left(r+7\right)\times 3
Use the distributive property to multiply r-1 by 4.
7r-3-4=\left(r+7\right)\times 3
Combine 3r and 4r to get 7r.
7r-7=\left(r+7\right)\times 3
Subtract 4 from -3 to get -7.
7r-7=3r+21
Use the distributive property to multiply r+7 by 3.
7r-7-3r=21
Subtract 3r from both sides.
4r-7=21
Combine 7r and -3r to get 4r.
4r=21+7
Add 7 to both sides.
4r=28
Add 21 and 7 to get 28.
r=\frac{28}{4}
Divide both sides by 4.
r=7
Divide 28 by 4 to get 7.
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