Solve for r
r = -\frac{21}{4} = -5\frac{1}{4} = -5.25
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-4r=5\times 4+1
Multiply both sides of the equation by 4.
-4r=20+1
Multiply 5 and 4 to get 20.
-4r=21
Add 20 and 1 to get 21.
r=\frac{21}{-4}
Divide both sides by -4.
r=-\frac{21}{4}
Fraction \frac{21}{-4} can be rewritten as -\frac{21}{4} by extracting the negative sign.
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