Solve for x
x=16
x=30
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\left(x-24\right)\left(22-x\right)=-24\times 2
Variable x cannot be equal to 24 since division by zero is not defined. Multiply both sides of the equation by 24\left(x-24\right), the least common multiple of 24,24-x.
46x-x^{2}-528=-24\times 2
Use the distributive property to multiply x-24 by 22-x and combine like terms.
46x-x^{2}-528=-48
Multiply -24 and 2 to get -48.
46x-x^{2}-528+48=0
Add 48 to both sides.
46x-x^{2}-480=0
Add -528 and 48 to get -480.
-x^{2}+46x-480=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{-46±\sqrt{46^{2}-4\left(-1\right)\left(-480\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 46 for b, and -480 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-46±\sqrt{2116-4\left(-1\right)\left(-480\right)}}{2\left(-1\right)}
Square 46.
x=\frac{-46±\sqrt{2116+4\left(-480\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-46±\sqrt{2116-1920}}{2\left(-1\right)}
Multiply 4 times -480.
x=\frac{-46±\sqrt{196}}{2\left(-1\right)}
Add 2116 to -1920.
x=\frac{-46±14}{2\left(-1\right)}
Take the square root of 196.
x=\frac{-46±14}{-2}
Multiply 2 times -1.
x=-\frac{32}{-2}
Now solve the equation x=\frac{-46±14}{-2} when ± is plus. Add -46 to 14.
x=16
Divide -32 by -2.
x=-\frac{60}{-2}
Now solve the equation x=\frac{-46±14}{-2} when ± is minus. Subtract 14 from -46.
x=30
Divide -60 by -2.
x=16 x=30
The equation is now solved.
\left(x-24\right)\left(22-x\right)=-24\times 2
Variable x cannot be equal to 24 since division by zero is not defined. Multiply both sides of the equation by 24\left(x-24\right), the least common multiple of 24,24-x.
46x-x^{2}-528=-24\times 2
Use the distributive property to multiply x-24 by 22-x and combine like terms.
46x-x^{2}-528=-48
Multiply -24 and 2 to get -48.
46x-x^{2}=-48+528
Add 528 to both sides.
46x-x^{2}=480
Add -48 and 528 to get 480.
-x^{2}+46x=480
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{-x^{2}+46x}{-1}=\frac{480}{-1}
Divide both sides by -1.
x^{2}+\frac{46}{-1}x=\frac{480}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-46x=\frac{480}{-1}
Divide 46 by -1.
x^{2}-46x=-480
Divide 480 by -1.
x^{2}-46x+\left(-23\right)^{2}=-480+\left(-23\right)^{2}
Divide -46, the coefficient of the x term, by 2 to get -23. Then add the square of -23 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-46x+529=-480+529
Square -23.
x^{2}-46x+529=49
Add -480 to 529.
\left(x-23\right)^{2}=49
Factor x^{2}-46x+529. 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-23\right)^{2}}=\sqrt{49}
Take the square root of both sides of the equation.
x-23=7 x-23=-7
Simplify.
x=30 x=16
Add 23 to both sides of the equation.
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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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