Solve for r
r=1
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21r-21=-6+6r
Use the distributive property to multiply 3 by 7r-7.
21r-21-6r=-6
Subtract 6r from both sides.
15r-21=-6
Combine 21r and -6r to get 15r.
15r=-6+21
Add 21 to both sides.
15r=15
Add -6 and 21 to get 15.
r=\frac{15}{15}
Divide both sides by 15.
r=1
Divide 15 by 15 to get 1.
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