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9d^{2}=\frac{81}{4}
Subtract 52 from \frac{289}{4} to get \frac{81}{4}.
9d^{2}-\frac{81}{4}=0
Subtract \frac{81}{4} from both sides.
4d^{2}-9=0
Divide both sides by \frac{9}{4}.
\left(2d-3\right)\left(2d+3\right)=0
Consider 4d^{2}-9. Rewrite 4d^{2}-9 as \left(2d\right)^{2}-3^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
d=\frac{3}{2} d=-\frac{3}{2}
To find equation solutions, solve 2d-3=0 and 2d+3=0.
9d^{2}=\frac{81}{4}
Subtract 52 from \frac{289}{4} to get \frac{81}{4}.
d^{2}=\frac{\frac{81}{4}}{9}
Divide both sides by 9.
d^{2}=\frac{81}{4\times 9}
Express \frac{\frac{81}{4}}{9} as a single fraction.
d^{2}=\frac{81}{36}
Multiply 4 and 9 to get 36.
d^{2}=\frac{9}{4}
Reduce the fraction \frac{81}{36} to lowest terms by extracting and canceling out 9.
d=\frac{3}{2} d=-\frac{3}{2}
Take the square root of both sides of the equation.
9d^{2}=\frac{81}{4}
Subtract 52 from \frac{289}{4} to get \frac{81}{4}.
9d^{2}-\frac{81}{4}=0
Subtract \frac{81}{4} from both sides.
d=\frac{0±\sqrt{0^{2}-4\times 9\left(-\frac{81}{4}\right)}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, 0 for b, and -\frac{81}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
d=\frac{0±\sqrt{-4\times 9\left(-\frac{81}{4}\right)}}{2\times 9}
Square 0.
d=\frac{0±\sqrt{-36\left(-\frac{81}{4}\right)}}{2\times 9}
Multiply -4 times 9.
d=\frac{0±\sqrt{729}}{2\times 9}
Multiply -36 times -\frac{81}{4}.
d=\frac{0±27}{2\times 9}
Take the square root of 729.
d=\frac{0±27}{18}
Multiply 2 times 9.
d=\frac{3}{2}
Now solve the equation d=\frac{0±27}{18} when ± is plus. Reduce the fraction \frac{27}{18} to lowest terms by extracting and canceling out 9.
d=-\frac{3}{2}
Now solve the equation d=\frac{0±27}{18} when ± is minus. Reduce the fraction \frac{-27}{18} to lowest terms by extracting and canceling out 9.
d=\frac{3}{2} d=-\frac{3}{2}
The equation is now solved.