Solve for x
x=\frac{2\sqrt{7}}{7}\approx 0.755928946
x=-\frac{2\sqrt{7}}{7}\approx -0.755928946
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4\left(x^{-1}+9x\right)=43x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
4x^{-1}+36x=43x
Use the distributive property to multiply 4 by x^{-1}+9x.
4x^{-1}+36x-43x=0
Subtract 43x from both sides.
4x^{-1}-7x=0
Combine 36x and -43x to get -7x.
-7x+4\times \frac{1}{x}=0
Reorder the terms.
-7xx+4\times 1=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-7x^{2}+4\times 1=0
Multiply x and x to get x^{2}.
-7x^{2}+4=0
Multiply 4 and 1 to get 4.
-7x^{2}=-4
Subtract 4 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-4}{-7}
Divide both sides by -7.
x^{2}=\frac{4}{7}
Fraction \frac{-4}{-7} can be simplified to \frac{4}{7} by removing the negative sign from both the numerator and the denominator.
x=\frac{2\sqrt{7}}{7} x=-\frac{2\sqrt{7}}{7}
Take the square root of both sides of the equation.
4\left(x^{-1}+9x\right)=43x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
4x^{-1}+36x=43x
Use the distributive property to multiply 4 by x^{-1}+9x.
4x^{-1}+36x-43x=0
Subtract 43x from both sides.
4x^{-1}-7x=0
Combine 36x and -43x to get -7x.
-7x+4\times \frac{1}{x}=0
Reorder the terms.
-7xx+4\times 1=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-7x^{2}+4\times 1=0
Multiply x and x to get x^{2}.
-7x^{2}+4=0
Multiply 4 and 1 to get 4.
x=\frac{0±\sqrt{0^{2}-4\left(-7\right)\times 4}}{2\left(-7\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -7 for a, 0 for b, and 4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-7\right)\times 4}}{2\left(-7\right)}
Square 0.
x=\frac{0±\sqrt{28\times 4}}{2\left(-7\right)}
Multiply -4 times -7.
x=\frac{0±\sqrt{112}}{2\left(-7\right)}
Multiply 28 times 4.
x=\frac{0±4\sqrt{7}}{2\left(-7\right)}
Take the square root of 112.
x=\frac{0±4\sqrt{7}}{-14}
Multiply 2 times -7.
x=-\frac{2\sqrt{7}}{7}
Now solve the equation x=\frac{0±4\sqrt{7}}{-14} when ± is plus.
x=\frac{2\sqrt{7}}{7}
Now solve the equation x=\frac{0±4\sqrt{7}}{-14} when ± is minus.
x=-\frac{2\sqrt{7}}{7} x=\frac{2\sqrt{7}}{7}
The equation is now solved.
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Matrix
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Simultaneous equation
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Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
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Limits
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