Solve for x (complex solution)
x=-3-i
x=-3+i
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Quadratic Equation
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\frac{ 5 }{ x } - \frac{ 5 }{ x-1 } = \frac{ x+6 }{ 2x-2 }
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\left(2x-2\right)\times 5-2x\times 5=x\left(x+6\right)
Variable x cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-1\right), the least common multiple of x,x-1,2x-2.
10x-10-2x\times 5=x\left(x+6\right)
Use the distributive property to multiply 2x-2 by 5.
10x-10-10x=x\left(x+6\right)
Multiply 2 and 5 to get 10.
10x-10-10x=x^{2}+6x
Use the distributive property to multiply x by x+6.
10x-10-10x-x^{2}=6x
Subtract x^{2} from both sides.
10x-10-10x-x^{2}-6x=0
Subtract 6x from both sides.
4x-10-10x-x^{2}=0
Combine 10x and -6x to get 4x.
-6x-10-x^{2}=0
Combine 4x and -10x to get -6x.
-x^{2}-6x-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{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\left(-1\right)\left(-10\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -6 for b, and -10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\left(-1\right)\left(-10\right)}}{2\left(-1\right)}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36+4\left(-10\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-\left(-6\right)±\sqrt{36-40}}{2\left(-1\right)}
Multiply 4 times -10.
x=\frac{-\left(-6\right)±\sqrt{-4}}{2\left(-1\right)}
Add 36 to -40.
x=\frac{-\left(-6\right)±2i}{2\left(-1\right)}
Take the square root of -4.
x=\frac{6±2i}{2\left(-1\right)}
The opposite of -6 is 6.
x=\frac{6±2i}{-2}
Multiply 2 times -1.
x=\frac{6+2i}{-2}
Now solve the equation x=\frac{6±2i}{-2} when ± is plus. Add 6 to 2i.
x=-3-i
Divide 6+2i by -2.
x=\frac{6-2i}{-2}
Now solve the equation x=\frac{6±2i}{-2} when ± is minus. Subtract 2i from 6.
x=-3+i
Divide 6-2i by -2.
x=-3-i x=-3+i
The equation is now solved.
\left(2x-2\right)\times 5-2x\times 5=x\left(x+6\right)
Variable x cannot be equal to any of the values 0,1 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-1\right), the least common multiple of x,x-1,2x-2.
10x-10-2x\times 5=x\left(x+6\right)
Use the distributive property to multiply 2x-2 by 5.
10x-10-10x=x\left(x+6\right)
Multiply 2 and 5 to get 10.
10x-10-10x=x^{2}+6x
Use the distributive property to multiply x by x+6.
10x-10-10x-x^{2}=6x
Subtract x^{2} from both sides.
10x-10-10x-x^{2}-6x=0
Subtract 6x from both sides.
4x-10-10x-x^{2}=0
Combine 10x and -6x to get 4x.
4x-10x-x^{2}=10
Add 10 to both sides. Anything plus zero gives itself.
-6x-x^{2}=10
Combine 4x and -10x to get -6x.
-x^{2}-6x=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{-x^{2}-6x}{-1}=\frac{10}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{6}{-1}\right)x=\frac{10}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+6x=\frac{10}{-1}
Divide -6 by -1.
x^{2}+6x=-10
Divide 10 by -1.
x^{2}+6x+3^{2}=-10+3^{2}
Divide 6, the coefficient of the x term, by 2 to get 3. Then add the square of 3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+6x+9=-10+9
Square 3.
x^{2}+6x+9=-1
Add -10 to 9.
\left(x+3\right)^{2}=-1
Factor x^{2}+6x+9. 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+3\right)^{2}}=\sqrt{-1}
Take the square root of both sides of the equation.
x+3=i x+3=-i
Simplify.
x=-3+i x=-3-i
Subtract 3 from both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}