Solve for x
x=12
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41x^{2}-984x+5904=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(-984\right)±\sqrt{\left(-984\right)^{2}-4\times 41\times 5904}}{2\times 41}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 41 for a, -984 for b, and 5904 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-984\right)±\sqrt{968256-4\times 41\times 5904}}{2\times 41}
Square -984.
x=\frac{-\left(-984\right)±\sqrt{968256-164\times 5904}}{2\times 41}
Multiply -4 times 41.
x=\frac{-\left(-984\right)±\sqrt{968256-968256}}{2\times 41}
Multiply -164 times 5904.
x=\frac{-\left(-984\right)±\sqrt{0}}{2\times 41}
Add 968256 to -968256.
x=-\frac{-984}{2\times 41}
Take the square root of 0.
x=\frac{984}{2\times 41}
The opposite of -984 is 984.
x=\frac{984}{82}
Multiply 2 times 41.
x=12
Divide 984 by 82.
41x^{2}-984x+5904=0
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.
41x^{2}-984x+5904-5904=-5904
Subtract 5904 from both sides of the equation.
41x^{2}-984x=-5904
Subtracting 5904 from itself leaves 0.
\frac{41x^{2}-984x}{41}=-\frac{5904}{41}
Divide both sides by 41.
x^{2}+\left(-\frac{984}{41}\right)x=-\frac{5904}{41}
Dividing by 41 undoes the multiplication by 41.
x^{2}-24x=-\frac{5904}{41}
Divide -984 by 41.
x^{2}-24x=-144
Divide -5904 by 41.
x^{2}-24x+\left(-12\right)^{2}=-144+\left(-12\right)^{2}
Divide -24, the coefficient of the x term, by 2 to get -12. Then add the square of -12 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-24x+144=-144+144
Square -12.
x^{2}-24x+144=0
Add -144 to 144.
\left(x-12\right)^{2}=0
Factor x^{2}-24x+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-12\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-12=0 x-12=0
Simplify.
x=12 x=12
Add 12 to both sides of the equation.
x=12
The equation is now solved. Solutions are the same.
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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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