Solve for x
x = \frac{5}{4} = 1\frac{1}{4} = 1.25
x = -\frac{5}{4} = -1\frac{1}{4} = -1.25
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100=8^{2}x^{2}
Calculate 10 to the power of 2 and get 100.
100=64x^{2}
Calculate 8 to the power of 2 and get 64.
64x^{2}=100
Swap sides so that all variable terms are on the left hand side.
64x^{2}-100=0
Subtract 100 from both sides.
16x^{2}-25=0
Divide both sides by 4.
\left(4x-5\right)\left(4x+5\right)=0
Consider 16x^{2}-25. Rewrite 16x^{2}-25 as \left(4x\right)^{2}-5^{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{5}{4} x=-\frac{5}{4}
To find equation solutions, solve 4x-5=0 and 4x+5=0.
100=8^{2}x^{2}
Calculate 10 to the power of 2 and get 100.
100=64x^{2}
Calculate 8 to the power of 2 and get 64.
64x^{2}=100
Swap sides so that all variable terms are on the left hand side.
x^{2}=\frac{100}{64}
Divide both sides by 64.
x^{2}=\frac{25}{16}
Reduce the fraction \frac{100}{64} to lowest terms by extracting and canceling out 4.
x=\frac{5}{4} x=-\frac{5}{4}
Take the square root of both sides of the equation.
100=8^{2}x^{2}
Calculate 10 to the power of 2 and get 100.
100=64x^{2}
Calculate 8 to the power of 2 and get 64.
64x^{2}=100
Swap sides so that all variable terms are on the left hand side.
64x^{2}-100=0
Subtract 100 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 64\left(-100\right)}}{2\times 64}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 64 for a, 0 for b, and -100 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 64\left(-100\right)}}{2\times 64}
Square 0.
x=\frac{0±\sqrt{-256\left(-100\right)}}{2\times 64}
Multiply -4 times 64.
x=\frac{0±\sqrt{25600}}{2\times 64}
Multiply -256 times -100.
x=\frac{0±160}{2\times 64}
Take the square root of 25600.
x=\frac{0±160}{128}
Multiply 2 times 64.
x=\frac{5}{4}
Now solve the equation x=\frac{0±160}{128} when ± is plus. Reduce the fraction \frac{160}{128} to lowest terms by extracting and canceling out 32.
x=-\frac{5}{4}
Now solve the equation x=\frac{0±160}{128} when ± is minus. Reduce the fraction \frac{-160}{128} to lowest terms by extracting and canceling out 32.
x=\frac{5}{4} x=-\frac{5}{4}
The equation is now solved.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}