Solve for x
x=\frac{\sqrt{201}}{12}+\frac{5}{4}\approx 2.431453907
x=-\frac{\sqrt{201}}{12}+\frac{5}{4}\approx 0.068546093
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2x\times 3x+1=15x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x.
6xx+1=15x
Multiply 2 and 3 to get 6.
6x^{2}+1=15x
Multiply x and x to get x^{2}.
6x^{2}+1-15x=0
Subtract 15x from both sides.
6x^{2}-15x+1=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-\left(-15\right)±\sqrt{\left(-15\right)^{2}-4\times 6}}{2\times 6}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 6 for a, -15 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-15\right)±\sqrt{225-4\times 6}}{2\times 6}
Square -15.
x=\frac{-\left(-15\right)±\sqrt{225-24}}{2\times 6}
Multiply -4 times 6.
x=\frac{-\left(-15\right)±\sqrt{201}}{2\times 6}
Add 225 to -24.
x=\frac{15±\sqrt{201}}{2\times 6}
The opposite of -15 is 15.
x=\frac{15±\sqrt{201}}{12}
Multiply 2 times 6.
x=\frac{\sqrt{201}+15}{12}
Now solve the equation x=\frac{15±\sqrt{201}}{12} when ± is plus. Add 15 to \sqrt{201}.
x=\frac{\sqrt{201}}{12}+\frac{5}{4}
Divide 15+\sqrt{201} by 12.
x=\frac{15-\sqrt{201}}{12}
Now solve the equation x=\frac{15±\sqrt{201}}{12} when ± is minus. Subtract \sqrt{201} from 15.
x=-\frac{\sqrt{201}}{12}+\frac{5}{4}
Divide 15-\sqrt{201} by 12.
x=\frac{\sqrt{201}}{12}+\frac{5}{4} x=-\frac{\sqrt{201}}{12}+\frac{5}{4}
The equation is now solved.
2x\times 3x+1=15x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x.
6xx+1=15x
Multiply 2 and 3 to get 6.
6x^{2}+1=15x
Multiply x and x to get x^{2}.
6x^{2}+1-15x=0
Subtract 15x from both sides.
6x^{2}-15x=-1
Subtract 1 from both sides. Anything subtracted from zero gives its negation.
\frac{6x^{2}-15x}{6}=-\frac{1}{6}
Divide both sides by 6.
x^{2}+\left(-\frac{15}{6}\right)x=-\frac{1}{6}
Dividing by 6 undoes the multiplication by 6.
x^{2}-\frac{5}{2}x=-\frac{1}{6}
Reduce the fraction \frac{-15}{6} to lowest terms by extracting and canceling out 3.
x^{2}-\frac{5}{2}x+\left(-\frac{5}{4}\right)^{2}=-\frac{1}{6}+\left(-\frac{5}{4}\right)^{2}
Divide -\frac{5}{2}, the coefficient of the x term, by 2 to get -\frac{5}{4}. Then add the square of -\frac{5}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{5}{2}x+\frac{25}{16}=-\frac{1}{6}+\frac{25}{16}
Square -\frac{5}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{5}{2}x+\frac{25}{16}=\frac{67}{48}
Add -\frac{1}{6} to \frac{25}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{5}{4}\right)^{2}=\frac{67}{48}
Factor x^{2}-\frac{5}{2}x+\frac{25}{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{5}{4}\right)^{2}}=\sqrt{\frac{67}{48}}
Take the square root of both sides of the equation.
x-\frac{5}{4}=\frac{\sqrt{201}}{12} x-\frac{5}{4}=-\frac{\sqrt{201}}{12}
Simplify.
x=\frac{\sqrt{201}}{12}+\frac{5}{4} x=-\frac{\sqrt{201}}{12}+\frac{5}{4}
Add \frac{5}{4} to both sides of the equation.
Examples
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{ 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}