Solve for r
r=7
r=-7
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1232=\frac{22}{21}r^{2}\times 24
Multiply \frac{1}{3} and \frac{22}{7} to get \frac{22}{21}.
1232=\frac{176}{7}r^{2}
Multiply \frac{22}{21} and 24 to get \frac{176}{7}.
\frac{176}{7}r^{2}=1232
Swap sides so that all variable terms are on the left hand side.
\frac{176}{7}r^{2}-1232=0
Subtract 1232 from both sides.
r^{2}-49=0
Divide both sides by \frac{176}{7}.
\left(r-7\right)\left(r+7\right)=0
Consider r^{2}-49. Rewrite r^{2}-49 as r^{2}-7^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
r=7 r=-7
To find equation solutions, solve r-7=0 and r+7=0.
1232=\frac{22}{21}r^{2}\times 24
Multiply \frac{1}{3} and \frac{22}{7} to get \frac{22}{21}.
1232=\frac{176}{7}r^{2}
Multiply \frac{22}{21} and 24 to get \frac{176}{7}.
\frac{176}{7}r^{2}=1232
Swap sides so that all variable terms are on the left hand side.
r^{2}=1232\times \frac{7}{176}
Multiply both sides by \frac{7}{176}, the reciprocal of \frac{176}{7}.
r^{2}=49
Multiply 1232 and \frac{7}{176} to get 49.
r=7 r=-7
Take the square root of both sides of the equation.
1232=\frac{22}{21}r^{2}\times 24
Multiply \frac{1}{3} and \frac{22}{7} to get \frac{22}{21}.
1232=\frac{176}{7}r^{2}
Multiply \frac{22}{21} and 24 to get \frac{176}{7}.
\frac{176}{7}r^{2}=1232
Swap sides so that all variable terms are on the left hand side.
\frac{176}{7}r^{2}-1232=0
Subtract 1232 from both sides.
r=\frac{0±\sqrt{0^{2}-4\times \frac{176}{7}\left(-1232\right)}}{2\times \frac{176}{7}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{176}{7} for a, 0 for b, and -1232 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
r=\frac{0±\sqrt{-4\times \frac{176}{7}\left(-1232\right)}}{2\times \frac{176}{7}}
Square 0.
r=\frac{0±\sqrt{-\frac{704}{7}\left(-1232\right)}}{2\times \frac{176}{7}}
Multiply -4 times \frac{176}{7}.
r=\frac{0±\sqrt{123904}}{2\times \frac{176}{7}}
Multiply -\frac{704}{7} times -1232.
r=\frac{0±352}{2\times \frac{176}{7}}
Take the square root of 123904.
r=\frac{0±352}{\frac{352}{7}}
Multiply 2 times \frac{176}{7}.
r=7
Now solve the equation r=\frac{0±352}{\frac{352}{7}} when ± is plus. Divide 352 by \frac{352}{7} by multiplying 352 by the reciprocal of \frac{352}{7}.
r=-7
Now solve the equation r=\frac{0±352}{\frac{352}{7}} when ± is minus. Divide -352 by \frac{352}{7} by multiplying -352 by the reciprocal of \frac{352}{7}.
r=7 r=-7
The equation is now solved.
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