Solve for x
x=2
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Quadratic Equation
5 problems similar to:
( 2 - x ) + 2 ( x - 2 ) ( 2 - x ) = ( 1 - x ) ( x - 2 )
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2-x+\left(2x-4\right)\left(2-x\right)=\left(1-x\right)\left(x-2\right)
Use the distributive property to multiply 2 by x-2.
2-x+8x-2x^{2}-8=\left(1-x\right)\left(x-2\right)
Use the distributive property to multiply 2x-4 by 2-x and combine like terms.
2+7x-2x^{2}-8=\left(1-x\right)\left(x-2\right)
Combine -x and 8x to get 7x.
-6+7x-2x^{2}=\left(1-x\right)\left(x-2\right)
Subtract 8 from 2 to get -6.
-6+7x-2x^{2}=3x-2-x^{2}
Use the distributive property to multiply 1-x by x-2 and combine like terms.
-6+7x-2x^{2}-3x=-2-x^{2}
Subtract 3x from both sides.
-6+4x-2x^{2}=-2-x^{2}
Combine 7x and -3x to get 4x.
-6+4x-2x^{2}-\left(-2\right)=-x^{2}
Subtract -2 from both sides.
-6+4x-2x^{2}+2=-x^{2}
The opposite of -2 is 2.
-6+4x-2x^{2}+2+x^{2}=0
Add x^{2} to both sides.
-4+4x-2x^{2}+x^{2}=0
Add -6 and 2 to get -4.
-4+4x-x^{2}=0
Combine -2x^{2} and x^{2} to get -x^{2}.
-x^{2}+4x-4=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{-4±\sqrt{4^{2}-4\left(-1\right)\left(-4\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 4 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-4±\sqrt{16-4\left(-1\right)\left(-4\right)}}{2\left(-1\right)}
Square 4.
x=\frac{-4±\sqrt{16+4\left(-4\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-4±\sqrt{16-16}}{2\left(-1\right)}
Multiply 4 times -4.
x=\frac{-4±\sqrt{0}}{2\left(-1\right)}
Add 16 to -16.
x=-\frac{4}{2\left(-1\right)}
Take the square root of 0.
x=-\frac{4}{-2}
Multiply 2 times -1.
x=2
Divide -4 by -2.
2-x+\left(2x-4\right)\left(2-x\right)=\left(1-x\right)\left(x-2\right)
Use the distributive property to multiply 2 by x-2.
2-x+8x-2x^{2}-8=\left(1-x\right)\left(x-2\right)
Use the distributive property to multiply 2x-4 by 2-x and combine like terms.
2+7x-2x^{2}-8=\left(1-x\right)\left(x-2\right)
Combine -x and 8x to get 7x.
-6+7x-2x^{2}=\left(1-x\right)\left(x-2\right)
Subtract 8 from 2 to get -6.
-6+7x-2x^{2}=3x-2-x^{2}
Use the distributive property to multiply 1-x by x-2 and combine like terms.
-6+7x-2x^{2}-3x=-2-x^{2}
Subtract 3x from both sides.
-6+4x-2x^{2}=-2-x^{2}
Combine 7x and -3x to get 4x.
-6+4x-2x^{2}+x^{2}=-2
Add x^{2} to both sides.
-6+4x-x^{2}=-2
Combine -2x^{2} and x^{2} to get -x^{2}.
4x-x^{2}=-2+6
Add 6 to both sides.
4x-x^{2}=4
Add -2 and 6 to get 4.
-x^{2}+4x=4
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}+4x}{-1}=\frac{4}{-1}
Divide both sides by -1.
x^{2}+\frac{4}{-1}x=\frac{4}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-4x=\frac{4}{-1}
Divide 4 by -1.
x^{2}-4x=-4
Divide 4 by -1.
x^{2}-4x+\left(-2\right)^{2}=-4+\left(-2\right)^{2}
Divide -4, the coefficient of the x term, by 2 to get -2. Then add the square of -2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-4x+4=-4+4
Square -2.
x^{2}-4x+4=0
Add -4 to 4.
\left(x-2\right)^{2}=0
Factor x^{2}-4x+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-2\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-2=0 x-2=0
Simplify.
x=2 x=2
Add 2 to both sides of the equation.
x=2
The equation is now solved. Solutions are the same.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}