Solve for x
x = \frac{\sqrt{161} - 1}{4} \approx 2.922144385
x=\frac{-\sqrt{161}-1}{4}\approx -3.422144385
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\left(2x-3\right)x=4\left(-x+5\right)
Variable x cannot be equal to 5 since division by zero is not defined. Multiply both sides of the equation by -x+5.
2x^{2}-3x=4\left(-x+5\right)
Use the distributive property to multiply 2x-3 by x.
2x^{2}-3x=-4x+20
Use the distributive property to multiply 4 by -x+5.
2x^{2}-3x+4x=20
Add 4x to both sides.
2x^{2}+x=20
Combine -3x and 4x to get x.
2x^{2}+x-20=0
Subtract 20 from both sides.
x=\frac{-1±\sqrt{1^{2}-4\times 2\left(-20\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 1 for b, and -20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\times 2\left(-20\right)}}{2\times 2}
Square 1.
x=\frac{-1±\sqrt{1-8\left(-20\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-1±\sqrt{1+160}}{2\times 2}
Multiply -8 times -20.
x=\frac{-1±\sqrt{161}}{2\times 2}
Add 1 to 160.
x=\frac{-1±\sqrt{161}}{4}
Multiply 2 times 2.
x=\frac{\sqrt{161}-1}{4}
Now solve the equation x=\frac{-1±\sqrt{161}}{4} when ± is plus. Add -1 to \sqrt{161}.
x=\frac{-\sqrt{161}-1}{4}
Now solve the equation x=\frac{-1±\sqrt{161}}{4} when ± is minus. Subtract \sqrt{161} from -1.
x=\frac{\sqrt{161}-1}{4} x=\frac{-\sqrt{161}-1}{4}
The equation is now solved.
\left(2x-3\right)x=4\left(-x+5\right)
Variable x cannot be equal to 5 since division by zero is not defined. Multiply both sides of the equation by -x+5.
2x^{2}-3x=4\left(-x+5\right)
Use the distributive property to multiply 2x-3 by x.
2x^{2}-3x=-4x+20
Use the distributive property to multiply 4 by -x+5.
2x^{2}-3x+4x=20
Add 4x to both sides.
2x^{2}+x=20
Combine -3x and 4x to get x.
\frac{2x^{2}+x}{2}=\frac{20}{2}
Divide both sides by 2.
x^{2}+\frac{1}{2}x=\frac{20}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+\frac{1}{2}x=10
Divide 20 by 2.
x^{2}+\frac{1}{2}x+\left(\frac{1}{4}\right)^{2}=10+\left(\frac{1}{4}\right)^{2}
Divide \frac{1}{2}, the coefficient of the x term, by 2 to get \frac{1}{4}. Then add the square of \frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{2}x+\frac{1}{16}=10+\frac{1}{16}
Square \frac{1}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{1}{2}x+\frac{1}{16}=\frac{161}{16}
Add 10 to \frac{1}{16}.
\left(x+\frac{1}{4}\right)^{2}=\frac{161}{16}
Factor x^{2}+\frac{1}{2}x+\frac{1}{16}. 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{1}{4}\right)^{2}}=\sqrt{\frac{161}{16}}
Take the square root of both sides of the equation.
x+\frac{1}{4}=\frac{\sqrt{161}}{4} x+\frac{1}{4}=-\frac{\sqrt{161}}{4}
Simplify.
x=\frac{\sqrt{161}-1}{4} x=\frac{-\sqrt{161}-1}{4}
Subtract \frac{1}{4} from both sides of the equation.
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
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Matrix
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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
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}