Solve for x
x=\frac{\sqrt{82}}{18}+\frac{4}{9}\approx 0.947521397
x=-\frac{\sqrt{82}}{18}+\frac{4}{9}\approx -0.058632508
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1=2\left(-x+1\right)+2x\times 2\left(-x+1\right)+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Variable x cannot be equal to 1 since division by zero is not defined. Multiply both sides of the equation by 2\left(-x+1\right).
1=-2x+2+2x\times 2\left(-x+1\right)+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Use the distributive property to multiply 2 by -x+1.
1=-2x+2+4x\left(-x+1\right)+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Multiply 2 and 2 to get 4.
1=-2x+2-4x^{2}+4x+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Use the distributive property to multiply 4x by -x+1.
1=2x+2-4x^{2}+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Combine -2x and 4x to get 2x.
1=2x+2-4x^{2}+6x\left(-x+1\right)+4x\times 2\left(-x+1\right)
Multiply 3 and 2 to get 6.
1=2x+2-4x^{2}-6x^{2}+6x+4x\times 2\left(-x+1\right)
Use the distributive property to multiply 6x by -x+1.
1=2x+2-10x^{2}+6x+4x\times 2\left(-x+1\right)
Combine -4x^{2} and -6x^{2} to get -10x^{2}.
1=8x+2-10x^{2}+4x\times 2\left(-x+1\right)
Combine 2x and 6x to get 8x.
1=8x+2-10x^{2}+8x\left(-x+1\right)
Multiply 4 and 2 to get 8.
1=8x+2-10x^{2}-8x^{2}+8x
Use the distributive property to multiply 8x by -x+1.
1=8x+2-18x^{2}+8x
Combine -10x^{2} and -8x^{2} to get -18x^{2}.
1=16x+2-18x^{2}
Combine 8x and 8x to get 16x.
16x+2-18x^{2}=1
Swap sides so that all variable terms are on the left hand side.
16x+2-18x^{2}-1=0
Subtract 1 from both sides.
16x+1-18x^{2}=0
Subtract 1 from 2 to get 1.
-18x^{2}+16x+1=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{-16±\sqrt{16^{2}-4\left(-18\right)}}{2\left(-18\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -18 for a, 16 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-16±\sqrt{256-4\left(-18\right)}}{2\left(-18\right)}
Square 16.
x=\frac{-16±\sqrt{256+72}}{2\left(-18\right)}
Multiply -4 times -18.
x=\frac{-16±\sqrt{328}}{2\left(-18\right)}
Add 256 to 72.
x=\frac{-16±2\sqrt{82}}{2\left(-18\right)}
Take the square root of 328.
x=\frac{-16±2\sqrt{82}}{-36}
Multiply 2 times -18.
x=\frac{2\sqrt{82}-16}{-36}
Now solve the equation x=\frac{-16±2\sqrt{82}}{-36} when ± is plus. Add -16 to 2\sqrt{82}.
x=-\frac{\sqrt{82}}{18}+\frac{4}{9}
Divide -16+2\sqrt{82} by -36.
x=\frac{-2\sqrt{82}-16}{-36}
Now solve the equation x=\frac{-16±2\sqrt{82}}{-36} when ± is minus. Subtract 2\sqrt{82} from -16.
x=\frac{\sqrt{82}}{18}+\frac{4}{9}
Divide -16-2\sqrt{82} by -36.
x=-\frac{\sqrt{82}}{18}+\frac{4}{9} x=\frac{\sqrt{82}}{18}+\frac{4}{9}
The equation is now solved.
1=2\left(-x+1\right)+2x\times 2\left(-x+1\right)+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Variable x cannot be equal to 1 since division by zero is not defined. Multiply both sides of the equation by 2\left(-x+1\right).
1=-2x+2+2x\times 2\left(-x+1\right)+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Use the distributive property to multiply 2 by -x+1.
1=-2x+2+4x\left(-x+1\right)+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Multiply 2 and 2 to get 4.
1=-2x+2-4x^{2}+4x+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Use the distributive property to multiply 4x by -x+1.
1=2x+2-4x^{2}+3x\times 2\left(-x+1\right)+4x\times 2\left(-x+1\right)
Combine -2x and 4x to get 2x.
1=2x+2-4x^{2}+6x\left(-x+1\right)+4x\times 2\left(-x+1\right)
Multiply 3 and 2 to get 6.
1=2x+2-4x^{2}-6x^{2}+6x+4x\times 2\left(-x+1\right)
Use the distributive property to multiply 6x by -x+1.
1=2x+2-10x^{2}+6x+4x\times 2\left(-x+1\right)
Combine -4x^{2} and -6x^{2} to get -10x^{2}.
1=8x+2-10x^{2}+4x\times 2\left(-x+1\right)
Combine 2x and 6x to get 8x.
1=8x+2-10x^{2}+8x\left(-x+1\right)
Multiply 4 and 2 to get 8.
1=8x+2-10x^{2}-8x^{2}+8x
Use the distributive property to multiply 8x by -x+1.
1=8x+2-18x^{2}+8x
Combine -10x^{2} and -8x^{2} to get -18x^{2}.
1=16x+2-18x^{2}
Combine 8x and 8x to get 16x.
16x+2-18x^{2}=1
Swap sides so that all variable terms are on the left hand side.
16x-18x^{2}=1-2
Subtract 2 from both sides.
16x-18x^{2}=-1
Subtract 2 from 1 to get -1.
-18x^{2}+16x=-1
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{-18x^{2}+16x}{-18}=-\frac{1}{-18}
Divide both sides by -18.
x^{2}+\frac{16}{-18}x=-\frac{1}{-18}
Dividing by -18 undoes the multiplication by -18.
x^{2}-\frac{8}{9}x=-\frac{1}{-18}
Reduce the fraction \frac{16}{-18} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{8}{9}x=\frac{1}{18}
Divide -1 by -18.
x^{2}-\frac{8}{9}x+\left(-\frac{4}{9}\right)^{2}=\frac{1}{18}+\left(-\frac{4}{9}\right)^{2}
Divide -\frac{8}{9}, the coefficient of the x term, by 2 to get -\frac{4}{9}. Then add the square of -\frac{4}{9} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{8}{9}x+\frac{16}{81}=\frac{1}{18}+\frac{16}{81}
Square -\frac{4}{9} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{8}{9}x+\frac{16}{81}=\frac{41}{162}
Add \frac{1}{18} to \frac{16}{81} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{4}{9}\right)^{2}=\frac{41}{162}
Factor x^{2}-\frac{8}{9}x+\frac{16}{81}. 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{4}{9}\right)^{2}}=\sqrt{\frac{41}{162}}
Take the square root of both sides of the equation.
x-\frac{4}{9}=\frac{\sqrt{82}}{18} x-\frac{4}{9}=-\frac{\sqrt{82}}{18}
Simplify.
x=\frac{\sqrt{82}}{18}+\frac{4}{9} x=-\frac{\sqrt{82}}{18}+\frac{4}{9}
Add \frac{4}{9} to both sides of the equation.
Examples
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{ 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}