Solve for x
x=20
x=-20
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\frac{169}{25}x^{2}=52^{2}
Combine \frac{144}{25}x^{2} and x^{2} to get \frac{169}{25}x^{2}.
\frac{169}{25}x^{2}=2704
Calculate 52 to the power of 2 and get 2704.
\frac{169}{25}x^{2}-2704=0
Subtract 2704 from both sides.
x^{2}-400=0
Divide both sides by \frac{169}{25}.
\left(x-20\right)\left(x+20\right)=0
Consider x^{2}-400. Rewrite x^{2}-400 as x^{2}-20^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=20 x=-20
To find equation solutions, solve x-20=0 and x+20=0.
\frac{169}{25}x^{2}=52^{2}
Combine \frac{144}{25}x^{2} and x^{2} to get \frac{169}{25}x^{2}.
\frac{169}{25}x^{2}=2704
Calculate 52 to the power of 2 and get 2704.
x^{2}=2704\times \frac{25}{169}
Multiply both sides by \frac{25}{169}, the reciprocal of \frac{169}{25}.
x^{2}=400
Multiply 2704 and \frac{25}{169} to get 400.
x=20 x=-20
Take the square root of both sides of the equation.
\frac{169}{25}x^{2}=52^{2}
Combine \frac{144}{25}x^{2} and x^{2} to get \frac{169}{25}x^{2}.
\frac{169}{25}x^{2}=2704
Calculate 52 to the power of 2 and get 2704.
\frac{169}{25}x^{2}-2704=0
Subtract 2704 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times \frac{169}{25}\left(-2704\right)}}{2\times \frac{169}{25}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{169}{25} for a, 0 for b, and -2704 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{169}{25}\left(-2704\right)}}{2\times \frac{169}{25}}
Square 0.
x=\frac{0±\sqrt{-\frac{676}{25}\left(-2704\right)}}{2\times \frac{169}{25}}
Multiply -4 times \frac{169}{25}.
x=\frac{0±\sqrt{\frac{1827904}{25}}}{2\times \frac{169}{25}}
Multiply -\frac{676}{25} times -2704.
x=\frac{0±\frac{1352}{5}}{2\times \frac{169}{25}}
Take the square root of \frac{1827904}{25}.
x=\frac{0±\frac{1352}{5}}{\frac{338}{25}}
Multiply 2 times \frac{169}{25}.
x=20
Now solve the equation x=\frac{0±\frac{1352}{5}}{\frac{338}{25}} when ± is plus.
x=-20
Now solve the equation x=\frac{0±\frac{1352}{5}}{\frac{338}{25}} when ± is minus.
x=20 x=-20
The equation is now solved.
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