Solve for x
x=2.31
x=-2.31
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3^{2}x^{2}=6.93^{2}
Expand \left(3x\right)^{2}.
9x^{2}=6.93^{2}
Calculate 3 to the power of 2 and get 9.
9x^{2}=48.0249
Calculate 6.93 to the power of 2 and get 48.0249.
9x^{2}-48.0249=0
Subtract 48.0249 from both sides.
\left(3x-\frac{693}{100}\right)\left(3x+\frac{693}{100}\right)=0
Consider 9x^{2}-48.0249. Rewrite 9x^{2}-48.0249 as \left(3x\right)^{2}-\left(\frac{693}{100}\right)^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=\frac{231}{100} x=-\frac{231}{100}
To find equation solutions, solve 3x-\frac{693}{100}=0 and 3x+\frac{693}{100}=0.
3^{2}x^{2}=6.93^{2}
Expand \left(3x\right)^{2}.
9x^{2}=6.93^{2}
Calculate 3 to the power of 2 and get 9.
9x^{2}=48.0249
Calculate 6.93 to the power of 2 and get 48.0249.
x^{2}=\frac{48.0249}{9}
Divide both sides by 9.
x^{2}=\frac{480249}{90000}
Expand \frac{48.0249}{9} by multiplying both numerator and the denominator by 10000.
x^{2}=\frac{53361}{10000}
Reduce the fraction \frac{480249}{90000} to lowest terms by extracting and canceling out 9.
x=\frac{231}{100} x=-\frac{231}{100}
Take the square root of both sides of the equation.
3^{2}x^{2}=6.93^{2}
Expand \left(3x\right)^{2}.
9x^{2}=6.93^{2}
Calculate 3 to the power of 2 and get 9.
9x^{2}=48.0249
Calculate 6.93 to the power of 2 and get 48.0249.
9x^{2}-48.0249=0
Subtract 48.0249 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 9\left(-48.0249\right)}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, 0 for b, and -48.0249 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 9\left(-48.0249\right)}}{2\times 9}
Square 0.
x=\frac{0±\sqrt{-36\left(-48.0249\right)}}{2\times 9}
Multiply -4 times 9.
x=\frac{0±\sqrt{1728.8964}}{2\times 9}
Multiply -36 times -48.0249.
x=\frac{0±\frac{2079}{50}}{2\times 9}
Take the square root of 1728.8964.
x=\frac{0±\frac{2079}{50}}{18}
Multiply 2 times 9.
x=\frac{231}{100}
Now solve the equation x=\frac{0±\frac{2079}{50}}{18} when ± is plus.
x=-\frac{231}{100}
Now solve the equation x=\frac{0±\frac{2079}{50}}{18} when ± is minus.
x=\frac{231}{100} x=-\frac{231}{100}
The equation is now solved.
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