Solve for r
r=4
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3\times 11=7r+5
Variable r cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3r, the least common multiple of r,3r.
33=7r+5
Multiply 3 and 11 to get 33.
7r+5=33
Swap sides so that all variable terms are on the left hand side.
7r=33-5
Subtract 5 from both sides.
7r=28
Subtract 5 from 33 to get 28.
r=\frac{28}{7}
Divide both sides by 7.
r=4
Divide 28 by 7 to get 4.
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