Solve for x
x = \frac{\sqrt{353} + 21}{4} \approx 9.947073557
x=\frac{21-\sqrt{353}}{4}\approx 0.552926443
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6x^{2}-13x+6=\left(2x+5\right)\left(2x-1\right)
Use the distributive property to multiply 3x-2 by 2x-3 and combine like terms.
6x^{2}-13x+6=4x^{2}+8x-5
Use the distributive property to multiply 2x+5 by 2x-1 and combine like terms.
6x^{2}-13x+6-4x^{2}=8x-5
Subtract 4x^{2} from both sides.
2x^{2}-13x+6=8x-5
Combine 6x^{2} and -4x^{2} to get 2x^{2}.
2x^{2}-13x+6-8x=-5
Subtract 8x from both sides.
2x^{2}-21x+6=-5
Combine -13x and -8x to get -21x.
2x^{2}-21x+6+5=0
Add 5 to both sides.
2x^{2}-21x+11=0
Add 6 and 5 to get 11.
x=\frac{-\left(-21\right)±\sqrt{\left(-21\right)^{2}-4\times 2\times 11}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -21 for b, and 11 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-21\right)±\sqrt{441-4\times 2\times 11}}{2\times 2}
Square -21.
x=\frac{-\left(-21\right)±\sqrt{441-8\times 11}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-21\right)±\sqrt{441-88}}{2\times 2}
Multiply -8 times 11.
x=\frac{-\left(-21\right)±\sqrt{353}}{2\times 2}
Add 441 to -88.
x=\frac{21±\sqrt{353}}{2\times 2}
The opposite of -21 is 21.
x=\frac{21±\sqrt{353}}{4}
Multiply 2 times 2.
x=\frac{\sqrt{353}+21}{4}
Now solve the equation x=\frac{21±\sqrt{353}}{4} when ± is plus. Add 21 to \sqrt{353}.
x=\frac{21-\sqrt{353}}{4}
Now solve the equation x=\frac{21±\sqrt{353}}{4} when ± is minus. Subtract \sqrt{353} from 21.
x=\frac{\sqrt{353}+21}{4} x=\frac{21-\sqrt{353}}{4}
The equation is now solved.
6x^{2}-13x+6=\left(2x+5\right)\left(2x-1\right)
Use the distributive property to multiply 3x-2 by 2x-3 and combine like terms.
6x^{2}-13x+6=4x^{2}+8x-5
Use the distributive property to multiply 2x+5 by 2x-1 and combine like terms.
6x^{2}-13x+6-4x^{2}=8x-5
Subtract 4x^{2} from both sides.
2x^{2}-13x+6=8x-5
Combine 6x^{2} and -4x^{2} to get 2x^{2}.
2x^{2}-13x+6-8x=-5
Subtract 8x from both sides.
2x^{2}-21x+6=-5
Combine -13x and -8x to get -21x.
2x^{2}-21x=-5-6
Subtract 6 from both sides.
2x^{2}-21x=-11
Subtract 6 from -5 to get -11.
\frac{2x^{2}-21x}{2}=-\frac{11}{2}
Divide both sides by 2.
x^{2}-\frac{21}{2}x=-\frac{11}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{21}{2}x+\left(-\frac{21}{4}\right)^{2}=-\frac{11}{2}+\left(-\frac{21}{4}\right)^{2}
Divide -\frac{21}{2}, the coefficient of the x term, by 2 to get -\frac{21}{4}. Then add the square of -\frac{21}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{21}{2}x+\frac{441}{16}=-\frac{11}{2}+\frac{441}{16}
Square -\frac{21}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{21}{2}x+\frac{441}{16}=\frac{353}{16}
Add -\frac{11}{2} to \frac{441}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{21}{4}\right)^{2}=\frac{353}{16}
Factor x^{2}-\frac{21}{2}x+\frac{441}{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{21}{4}\right)^{2}}=\sqrt{\frac{353}{16}}
Take the square root of both sides of the equation.
x-\frac{21}{4}=\frac{\sqrt{353}}{4} x-\frac{21}{4}=-\frac{\sqrt{353}}{4}
Simplify.
x=\frac{\sqrt{353}+21}{4} x=\frac{21-\sqrt{353}}{4}
Add \frac{21}{4} to both sides of the equation.
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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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