Solve for x
x=\frac{3\sqrt{10}}{10}\approx 0.948683298
x=-\frac{3\sqrt{10}}{10}\approx -0.948683298
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3\times 3=x\times 10x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 6x, the least common multiple of 2x,6.
9=x\times 10x
Multiply 3 and 3 to get 9.
9=x^{2}\times 10
Multiply x and x to get x^{2}.
x^{2}\times 10=9
Swap sides so that all variable terms are on the left hand side.
x^{2}=\frac{9}{10}
Divide both sides by 10.
x=\frac{3\sqrt{10}}{10} x=-\frac{3\sqrt{10}}{10}
Take the square root of both sides of the equation.
3\times 3=x\times 10x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 6x, the least common multiple of 2x,6.
9=x\times 10x
Multiply 3 and 3 to get 9.
9=x^{2}\times 10
Multiply x and x to get x^{2}.
x^{2}\times 10=9
Swap sides so that all variable terms are on the left hand side.
x^{2}\times 10-9=0
Subtract 9 from both sides.
10x^{2}-9=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times 10\left(-9\right)}}{2\times 10}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 10 for a, 0 for b, and -9 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 10\left(-9\right)}}{2\times 10}
Square 0.
x=\frac{0±\sqrt{-40\left(-9\right)}}{2\times 10}
Multiply -4 times 10.
x=\frac{0±\sqrt{360}}{2\times 10}
Multiply -40 times -9.
x=\frac{0±6\sqrt{10}}{2\times 10}
Take the square root of 360.
x=\frac{0±6\sqrt{10}}{20}
Multiply 2 times 10.
x=\frac{3\sqrt{10}}{10}
Now solve the equation x=\frac{0±6\sqrt{10}}{20} when ± is plus.
x=-\frac{3\sqrt{10}}{10}
Now solve the equation x=\frac{0±6\sqrt{10}}{20} when ± is minus.
x=\frac{3\sqrt{10}}{10} x=-\frac{3\sqrt{10}}{10}
The equation is now solved.
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Simultaneous equation
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Differentiation
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Integration
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Limits
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