Solve for x
x=\frac{4}{5}=0.8
x=-\frac{4}{5}=-0.8
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x^{2}+\frac{9}{25}=1
Calculate \frac{3}{5} to the power of 2 and get \frac{9}{25}.
x^{2}+\frac{9}{25}-1=0
Subtract 1 from both sides.
x^{2}-\frac{16}{25}=0
Subtract 1 from \frac{9}{25} to get -\frac{16}{25}.
25x^{2}-16=0
Multiply both sides by 25.
\left(5x-4\right)\left(5x+4\right)=0
Consider 25x^{2}-16. Rewrite 25x^{2}-16 as \left(5x\right)^{2}-4^{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{4}{5} x=-\frac{4}{5}
To find equation solutions, solve 5x-4=0 and 5x+4=0.
x^{2}+\frac{9}{25}=1
Calculate \frac{3}{5} to the power of 2 and get \frac{9}{25}.
x^{2}=1-\frac{9}{25}
Subtract \frac{9}{25} from both sides.
x^{2}=\frac{16}{25}
Subtract \frac{9}{25} from 1 to get \frac{16}{25}.
x=\frac{4}{5} x=-\frac{4}{5}
Take the square root of both sides of the equation.
x^{2}+\frac{9}{25}=1
Calculate \frac{3}{5} to the power of 2 and get \frac{9}{25}.
x^{2}+\frac{9}{25}-1=0
Subtract 1 from both sides.
x^{2}-\frac{16}{25}=0
Subtract 1 from \frac{9}{25} to get -\frac{16}{25}.
x=\frac{0±\sqrt{0^{2}-4\left(-\frac{16}{25}\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -\frac{16}{25} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-\frac{16}{25}\right)}}{2}
Square 0.
x=\frac{0±\sqrt{\frac{64}{25}}}{2}
Multiply -4 times -\frac{16}{25}.
x=\frac{0±\frac{8}{5}}{2}
Take the square root of \frac{64}{25}.
x=\frac{4}{5}
Now solve the equation x=\frac{0±\frac{8}{5}}{2} when ± is plus.
x=-\frac{4}{5}
Now solve the equation x=\frac{0±\frac{8}{5}}{2} when ± is minus.
x=\frac{4}{5} x=-\frac{4}{5}
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}