( 15 \quad 3 x ^ { 2 } = 27 x
Solve for x
x=\frac{3}{17}\approx 0.176470588
x=0
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153x^{2}-27x=0
Subtract 27x from both sides.
x\left(153x-27\right)=0
Factor out x.
x=0 x=\frac{3}{17}
To find equation solutions, solve x=0 and 153x-27=0.
153x^{2}-27x=0
Subtract 27x from both sides.
x=\frac{-\left(-27\right)±\sqrt{\left(-27\right)^{2}}}{2\times 153}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 153 for a, -27 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-27\right)±27}{2\times 153}
Take the square root of \left(-27\right)^{2}.
x=\frac{27±27}{2\times 153}
The opposite of -27 is 27.
x=\frac{27±27}{306}
Multiply 2 times 153.
x=\frac{54}{306}
Now solve the equation x=\frac{27±27}{306} when ± is plus. Add 27 to 27.
x=\frac{3}{17}
Reduce the fraction \frac{54}{306} to lowest terms by extracting and canceling out 18.
x=\frac{0}{306}
Now solve the equation x=\frac{27±27}{306} when ± is minus. Subtract 27 from 27.
x=0
Divide 0 by 306.
x=\frac{3}{17} x=0
The equation is now solved.
153x^{2}-27x=0
Subtract 27x from both sides.
\frac{153x^{2}-27x}{153}=\frac{0}{153}
Divide both sides by 153.
x^{2}+\left(-\frac{27}{153}\right)x=\frac{0}{153}
Dividing by 153 undoes the multiplication by 153.
x^{2}-\frac{3}{17}x=\frac{0}{153}
Reduce the fraction \frac{-27}{153} to lowest terms by extracting and canceling out 9.
x^{2}-\frac{3}{17}x=0
Divide 0 by 153.
x^{2}-\frac{3}{17}x+\left(-\frac{3}{34}\right)^{2}=\left(-\frac{3}{34}\right)^{2}
Divide -\frac{3}{17}, the coefficient of the x term, by 2 to get -\frac{3}{34}. Then add the square of -\frac{3}{34} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{17}x+\frac{9}{1156}=\frac{9}{1156}
Square -\frac{3}{34} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{3}{34}\right)^{2}=\frac{9}{1156}
Factor x^{2}-\frac{3}{17}x+\frac{9}{1156}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{3}{34}\right)^{2}}=\sqrt{\frac{9}{1156}}
Take the square root of both sides of the equation.
x-\frac{3}{34}=\frac{3}{34} x-\frac{3}{34}=-\frac{3}{34}
Simplify.
x=\frac{3}{17} x=0
Add \frac{3}{34} to both sides of the equation.
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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
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