Solve for x
x=-47
x=14
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\left(x+11\right)\left(22+x\right)=15\times 60
Variable x cannot be equal to -11 since division by zero is not defined. Multiply both sides of the equation by 30\left(x+11\right), the least common multiple of 30,22+2x.
33x+x^{2}+242=15\times 60
Use the distributive property to multiply x+11 by 22+x and combine like terms.
33x+x^{2}+242=900
Multiply 15 and 60 to get 900.
33x+x^{2}+242-900=0
Subtract 900 from both sides.
33x+x^{2}-658=0
Subtract 900 from 242 to get -658.
x^{2}+33x-658=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{-33±\sqrt{33^{2}-4\left(-658\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 33 for b, and -658 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-33±\sqrt{1089-4\left(-658\right)}}{2}
Square 33.
x=\frac{-33±\sqrt{1089+2632}}{2}
Multiply -4 times -658.
x=\frac{-33±\sqrt{3721}}{2}
Add 1089 to 2632.
x=\frac{-33±61}{2}
Take the square root of 3721.
x=\frac{28}{2}
Now solve the equation x=\frac{-33±61}{2} when ± is plus. Add -33 to 61.
x=14
Divide 28 by 2.
x=-\frac{94}{2}
Now solve the equation x=\frac{-33±61}{2} when ± is minus. Subtract 61 from -33.
x=-47
Divide -94 by 2.
x=14 x=-47
The equation is now solved.
\left(x+11\right)\left(22+x\right)=15\times 60
Variable x cannot be equal to -11 since division by zero is not defined. Multiply both sides of the equation by 30\left(x+11\right), the least common multiple of 30,22+2x.
33x+x^{2}+242=15\times 60
Use the distributive property to multiply x+11 by 22+x and combine like terms.
33x+x^{2}+242=900
Multiply 15 and 60 to get 900.
33x+x^{2}=900-242
Subtract 242 from both sides.
33x+x^{2}=658
Subtract 242 from 900 to get 658.
x^{2}+33x=658
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.
x^{2}+33x+\left(\frac{33}{2}\right)^{2}=658+\left(\frac{33}{2}\right)^{2}
Divide 33, the coefficient of the x term, by 2 to get \frac{33}{2}. Then add the square of \frac{33}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+33x+\frac{1089}{4}=658+\frac{1089}{4}
Square \frac{33}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+33x+\frac{1089}{4}=\frac{3721}{4}
Add 658 to \frac{1089}{4}.
\left(x+\frac{33}{2}\right)^{2}=\frac{3721}{4}
Factor x^{2}+33x+\frac{1089}{4}. 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{33}{2}\right)^{2}}=\sqrt{\frac{3721}{4}}
Take the square root of both sides of the equation.
x+\frac{33}{2}=\frac{61}{2} x+\frac{33}{2}=-\frac{61}{2}
Simplify.
x=14 x=-47
Subtract \frac{33}{2} from 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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