Solve for x (complex solution)
x=\frac{-101+\sqrt{15839}i}{12}\approx -8.416666667+10.487757413i
x=\frac{-\sqrt{15839}i-101}{12}\approx -8.416666667-10.487757413i
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\left(6x+105\right)\left(11+x\right)+105\times 11=35\left(2x+35\right)
Variable x cannot be equal to -\frac{35}{2} since division by zero is not defined. Multiply both sides of the equation by 105\left(2x+35\right), the least common multiple of 35,35+2x,3.
171x+6x^{2}+1155+105\times 11=35\left(2x+35\right)
Use the distributive property to multiply 6x+105 by 11+x and combine like terms.
171x+6x^{2}+1155+1155=35\left(2x+35\right)
Multiply 105 and 11 to get 1155.
171x+6x^{2}+2310=35\left(2x+35\right)
Add 1155 and 1155 to get 2310.
171x+6x^{2}+2310=70x+1225
Use the distributive property to multiply 35 by 2x+35.
171x+6x^{2}+2310-70x=1225
Subtract 70x from both sides.
101x+6x^{2}+2310=1225
Combine 171x and -70x to get 101x.
101x+6x^{2}+2310-1225=0
Subtract 1225 from both sides.
101x+6x^{2}+1085=0
Subtract 1225 from 2310 to get 1085.
6x^{2}+101x+1085=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{-101±\sqrt{101^{2}-4\times 6\times 1085}}{2\times 6}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 6 for a, 101 for b, and 1085 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-101±\sqrt{10201-4\times 6\times 1085}}{2\times 6}
Square 101.
x=\frac{-101±\sqrt{10201-24\times 1085}}{2\times 6}
Multiply -4 times 6.
x=\frac{-101±\sqrt{10201-26040}}{2\times 6}
Multiply -24 times 1085.
x=\frac{-101±\sqrt{-15839}}{2\times 6}
Add 10201 to -26040.
x=\frac{-101±\sqrt{15839}i}{2\times 6}
Take the square root of -15839.
x=\frac{-101±\sqrt{15839}i}{12}
Multiply 2 times 6.
x=\frac{-101+\sqrt{15839}i}{12}
Now solve the equation x=\frac{-101±\sqrt{15839}i}{12} when ± is plus. Add -101 to i\sqrt{15839}.
x=\frac{-\sqrt{15839}i-101}{12}
Now solve the equation x=\frac{-101±\sqrt{15839}i}{12} when ± is minus. Subtract i\sqrt{15839} from -101.
x=\frac{-101+\sqrt{15839}i}{12} x=\frac{-\sqrt{15839}i-101}{12}
The equation is now solved.
\left(6x+105\right)\left(11+x\right)+105\times 11=35\left(2x+35\right)
Variable x cannot be equal to -\frac{35}{2} since division by zero is not defined. Multiply both sides of the equation by 105\left(2x+35\right), the least common multiple of 35,35+2x,3.
171x+6x^{2}+1155+105\times 11=35\left(2x+35\right)
Use the distributive property to multiply 6x+105 by 11+x and combine like terms.
171x+6x^{2}+1155+1155=35\left(2x+35\right)
Multiply 105 and 11 to get 1155.
171x+6x^{2}+2310=35\left(2x+35\right)
Add 1155 and 1155 to get 2310.
171x+6x^{2}+2310=70x+1225
Use the distributive property to multiply 35 by 2x+35.
171x+6x^{2}+2310-70x=1225
Subtract 70x from both sides.
101x+6x^{2}+2310=1225
Combine 171x and -70x to get 101x.
101x+6x^{2}=1225-2310
Subtract 2310 from both sides.
101x+6x^{2}=-1085
Subtract 2310 from 1225 to get -1085.
6x^{2}+101x=-1085
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}+101x}{6}=-\frac{1085}{6}
Divide both sides by 6.
x^{2}+\frac{101}{6}x=-\frac{1085}{6}
Dividing by 6 undoes the multiplication by 6.
x^{2}+\frac{101}{6}x+\left(\frac{101}{12}\right)^{2}=-\frac{1085}{6}+\left(\frac{101}{12}\right)^{2}
Divide \frac{101}{6}, the coefficient of the x term, by 2 to get \frac{101}{12}. Then add the square of \frac{101}{12} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{101}{6}x+\frac{10201}{144}=-\frac{1085}{6}+\frac{10201}{144}
Square \frac{101}{12} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{101}{6}x+\frac{10201}{144}=-\frac{15839}{144}
Add -\frac{1085}{6} to \frac{10201}{144} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{101}{12}\right)^{2}=-\frac{15839}{144}
Factor x^{2}+\frac{101}{6}x+\frac{10201}{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{101}{12}\right)^{2}}=\sqrt{-\frac{15839}{144}}
Take the square root of both sides of the equation.
x+\frac{101}{12}=\frac{\sqrt{15839}i}{12} x+\frac{101}{12}=-\frac{\sqrt{15839}i}{12}
Simplify.
x=\frac{-101+\sqrt{15839}i}{12} x=\frac{-\sqrt{15839}i-101}{12}
Subtract \frac{101}{12} from both sides of the equation.
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Simultaneous equation
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Differentiation
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Limits
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