Solve for x
x = \frac{\sqrt{385} + 25}{12} \approx 3.718451406
x=\frac{25-\sqrt{385}}{12}\approx 0.448215261
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6x-12-2\left(x+2\right)-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Multiply both sides of the equation by 6, the least common multiple of 3,2.
6x-12-2x-4-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Use the distributive property to multiply -2 by x+2.
4x-12-4-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Combine 6x and -2x to get 4x.
4x-16-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Subtract 4 from -12 to get -16.
4x-16-3x+6=6\left(x-2\right)^{2}-24
Use the distributive property to multiply -3 by x-2.
x-16+6=6\left(x-2\right)^{2}-24
Combine 4x and -3x to get x.
x-10=6\left(x-2\right)^{2}-24
Add -16 and 6 to get -10.
x-10=6\left(x^{2}-4x+4\right)-24
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x-10=6x^{2}-24x+24-24
Use the distributive property to multiply 6 by x^{2}-4x+4.
x-10=6x^{2}-24x
Subtract 24 from 24 to get 0.
x-10-6x^{2}=-24x
Subtract 6x^{2} from both sides.
x-10-6x^{2}+24x=0
Add 24x to both sides.
25x-10-6x^{2}=0
Combine x and 24x to get 25x.
-6x^{2}+25x-10=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{-25±\sqrt{25^{2}-4\left(-6\right)\left(-10\right)}}{2\left(-6\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -6 for a, 25 for b, and -10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-25±\sqrt{625-4\left(-6\right)\left(-10\right)}}{2\left(-6\right)}
Square 25.
x=\frac{-25±\sqrt{625+24\left(-10\right)}}{2\left(-6\right)}
Multiply -4 times -6.
x=\frac{-25±\sqrt{625-240}}{2\left(-6\right)}
Multiply 24 times -10.
x=\frac{-25±\sqrt{385}}{2\left(-6\right)}
Add 625 to -240.
x=\frac{-25±\sqrt{385}}{-12}
Multiply 2 times -6.
x=\frac{\sqrt{385}-25}{-12}
Now solve the equation x=\frac{-25±\sqrt{385}}{-12} when ± is plus. Add -25 to \sqrt{385}.
x=\frac{25-\sqrt{385}}{12}
Divide -25+\sqrt{385} by -12.
x=\frac{-\sqrt{385}-25}{-12}
Now solve the equation x=\frac{-25±\sqrt{385}}{-12} when ± is minus. Subtract \sqrt{385} from -25.
x=\frac{\sqrt{385}+25}{12}
Divide -25-\sqrt{385} by -12.
x=\frac{25-\sqrt{385}}{12} x=\frac{\sqrt{385}+25}{12}
The equation is now solved.
6x-12-2\left(x+2\right)-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Multiply both sides of the equation by 6, the least common multiple of 3,2.
6x-12-2x-4-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Use the distributive property to multiply -2 by x+2.
4x-12-4-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Combine 6x and -2x to get 4x.
4x-16-3\left(x-2\right)=6\left(x-2\right)^{2}-24
Subtract 4 from -12 to get -16.
4x-16-3x+6=6\left(x-2\right)^{2}-24
Use the distributive property to multiply -3 by x-2.
x-16+6=6\left(x-2\right)^{2}-24
Combine 4x and -3x to get x.
x-10=6\left(x-2\right)^{2}-24
Add -16 and 6 to get -10.
x-10=6\left(x^{2}-4x+4\right)-24
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x-10=6x^{2}-24x+24-24
Use the distributive property to multiply 6 by x^{2}-4x+4.
x-10=6x^{2}-24x
Subtract 24 from 24 to get 0.
x-10-6x^{2}=-24x
Subtract 6x^{2} from both sides.
x-10-6x^{2}+24x=0
Add 24x to both sides.
25x-10-6x^{2}=0
Combine x and 24x to get 25x.
25x-6x^{2}=10
Add 10 to both sides. Anything plus zero gives itself.
-6x^{2}+25x=10
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-6x^{2}+25x}{-6}=\frac{10}{-6}
Divide both sides by -6.
x^{2}+\frac{25}{-6}x=\frac{10}{-6}
Dividing by -6 undoes the multiplication by -6.
x^{2}-\frac{25}{6}x=\frac{10}{-6}
Divide 25 by -6.
x^{2}-\frac{25}{6}x=-\frac{5}{3}
Reduce the fraction \frac{10}{-6} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{25}{6}x+\left(-\frac{25}{12}\right)^{2}=-\frac{5}{3}+\left(-\frac{25}{12}\right)^{2}
Divide -\frac{25}{6}, the coefficient of the x term, by 2 to get -\frac{25}{12}. Then add the square of -\frac{25}{12} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{25}{6}x+\frac{625}{144}=-\frac{5}{3}+\frac{625}{144}
Square -\frac{25}{12} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{25}{6}x+\frac{625}{144}=\frac{385}{144}
Add -\frac{5}{3} to \frac{625}{144} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{25}{12}\right)^{2}=\frac{385}{144}
Factor x^{2}-\frac{25}{6}x+\frac{625}{144}. 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{25}{12}\right)^{2}}=\sqrt{\frac{385}{144}}
Take the square root of both sides of the equation.
x-\frac{25}{12}=\frac{\sqrt{385}}{12} x-\frac{25}{12}=-\frac{\sqrt{385}}{12}
Simplify.
x=\frac{\sqrt{385}+25}{12} x=\frac{25-\sqrt{385}}{12}
Add \frac{25}{12} to both sides of the equation.
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Simultaneous equation
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Limits
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