Solve for x
x=\sqrt{5}+1\approx 3.236067977
x=1-\sqrt{5}\approx -1.236067977
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Quadratic Equation
5 problems similar to:
\frac{ x+4 \left( 2+ \frac{ 4 }{ x } \right) }{ 2x } = 2.5
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x+4\left(2+\frac{4}{x}\right)=5x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x.
x+4\left(\frac{2x}{x}+\frac{4}{x}\right)=5x
To add or subtract expressions, expand them to make their denominators the same. Multiply 2 times \frac{x}{x}.
x+4\times \frac{2x+4}{x}=5x
Since \frac{2x}{x} and \frac{4}{x} have the same denominator, add them by adding their numerators.
x+\frac{4\left(2x+4\right)}{x}=5x
Express 4\times \frac{2x+4}{x} as a single fraction.
\frac{xx}{x}+\frac{4\left(2x+4\right)}{x}=5x
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{x}{x}.
\frac{xx+4\left(2x+4\right)}{x}=5x
Since \frac{xx}{x} and \frac{4\left(2x+4\right)}{x} have the same denominator, add them by adding their numerators.
\frac{x^{2}+8x+16}{x}=5x
Do the multiplications in xx+4\left(2x+4\right).
\frac{x^{2}+8x+16}{x}-5x=0
Subtract 5x from both sides.
\frac{x^{2}+8x+16}{x}+\frac{-5xx}{x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -5x times \frac{x}{x}.
\frac{x^{2}+8x+16-5xx}{x}=0
Since \frac{x^{2}+8x+16}{x} and \frac{-5xx}{x} have the same denominator, add them by adding their numerators.
\frac{x^{2}+8x+16-5x^{2}}{x}=0
Do the multiplications in x^{2}+8x+16-5xx.
\frac{-4x^{2}+8x+16}{x}=0
Combine like terms in x^{2}+8x+16-5x^{2}.
-4x^{2}+8x+16=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x=\frac{-8±\sqrt{8^{2}-4\left(-4\right)\times 16}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, 8 for b, and 16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\left(-4\right)\times 16}}{2\left(-4\right)}
Square 8.
x=\frac{-8±\sqrt{64+16\times 16}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{-8±\sqrt{64+256}}{2\left(-4\right)}
Multiply 16 times 16.
x=\frac{-8±\sqrt{320}}{2\left(-4\right)}
Add 64 to 256.
x=\frac{-8±8\sqrt{5}}{2\left(-4\right)}
Take the square root of 320.
x=\frac{-8±8\sqrt{5}}{-8}
Multiply 2 times -4.
x=\frac{8\sqrt{5}-8}{-8}
Now solve the equation x=\frac{-8±8\sqrt{5}}{-8} when ± is plus. Add -8 to 8\sqrt{5}.
x=1-\sqrt{5}
Divide -8+8\sqrt{5} by -8.
x=\frac{-8\sqrt{5}-8}{-8}
Now solve the equation x=\frac{-8±8\sqrt{5}}{-8} when ± is minus. Subtract 8\sqrt{5} from -8.
x=\sqrt{5}+1
Divide -8-8\sqrt{5} by -8.
x=1-\sqrt{5} x=\sqrt{5}+1
The equation is now solved.
x+4\left(2+\frac{4}{x}\right)=5x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2x.
x+4\left(\frac{2x}{x}+\frac{4}{x}\right)=5x
To add or subtract expressions, expand them to make their denominators the same. Multiply 2 times \frac{x}{x}.
x+4\times \frac{2x+4}{x}=5x
Since \frac{2x}{x} and \frac{4}{x} have the same denominator, add them by adding their numerators.
x+\frac{4\left(2x+4\right)}{x}=5x
Express 4\times \frac{2x+4}{x} as a single fraction.
\frac{xx}{x}+\frac{4\left(2x+4\right)}{x}=5x
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{x}{x}.
\frac{xx+4\left(2x+4\right)}{x}=5x
Since \frac{xx}{x} and \frac{4\left(2x+4\right)}{x} have the same denominator, add them by adding their numerators.
\frac{x^{2}+8x+16}{x}=5x
Do the multiplications in xx+4\left(2x+4\right).
\frac{x^{2}+8x+16}{x}-5x=0
Subtract 5x from both sides.
\frac{x^{2}+8x+16}{x}+\frac{-5xx}{x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -5x times \frac{x}{x}.
\frac{x^{2}+8x+16-5xx}{x}=0
Since \frac{x^{2}+8x+16}{x} and \frac{-5xx}{x} have the same denominator, add them by adding their numerators.
\frac{x^{2}+8x+16-5x^{2}}{x}=0
Do the multiplications in x^{2}+8x+16-5xx.
\frac{-4x^{2}+8x+16}{x}=0
Combine like terms in x^{2}+8x+16-5x^{2}.
-4x^{2}+8x+16=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-4x^{2}+8x=-16
Subtract 16 from both sides. Anything subtracted from zero gives its negation.
\frac{-4x^{2}+8x}{-4}=-\frac{16}{-4}
Divide both sides by -4.
x^{2}+\frac{8}{-4}x=-\frac{16}{-4}
Dividing by -4 undoes the multiplication by -4.
x^{2}-2x=-\frac{16}{-4}
Divide 8 by -4.
x^{2}-2x=4
Divide -16 by -4.
x^{2}-2x+1=4+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=5
Add 4 to 1.
\left(x-1\right)^{2}=5
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{5}
Take the square root of both sides of the equation.
x-1=\sqrt{5} x-1=-\sqrt{5}
Simplify.
x=\sqrt{5}+1 x=1-\sqrt{5}
Add 1 to both sides of the equation.
Examples
Quadratic equation
{ 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}