Solve for x
x=2
x=0
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x^{2}+16-16x+4x^{2}=\left(4-x\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4-2x\right)^{2}.
5x^{2}+16-16x=\left(4-x\right)^{2}
Combine x^{2} and 4x^{2} to get 5x^{2}.
5x^{2}+16-16x=16-8x+x^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4-x\right)^{2}.
5x^{2}+16-16x-16=-8x+x^{2}
Subtract 16 from both sides.
5x^{2}-16x=-8x+x^{2}
Subtract 16 from 16 to get 0.
5x^{2}-16x+8x=x^{2}
Add 8x to both sides.
5x^{2}-8x=x^{2}
Combine -16x and 8x to get -8x.
5x^{2}-8x-x^{2}=0
Subtract x^{2} from both sides.
4x^{2}-8x=0
Combine 5x^{2} and -x^{2} to get 4x^{2}.
x\left(4x-8\right)=0
Factor out x.
x=0 x=2
To find equation solutions, solve x=0 and 4x-8=0.
x^{2}+16-16x+4x^{2}=\left(4-x\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4-2x\right)^{2}.
5x^{2}+16-16x=\left(4-x\right)^{2}
Combine x^{2} and 4x^{2} to get 5x^{2}.
5x^{2}+16-16x=16-8x+x^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4-x\right)^{2}.
5x^{2}+16-16x-16=-8x+x^{2}
Subtract 16 from both sides.
5x^{2}-16x=-8x+x^{2}
Subtract 16 from 16 to get 0.
5x^{2}-16x+8x=x^{2}
Add 8x to both sides.
5x^{2}-8x=x^{2}
Combine -16x and 8x to get -8x.
5x^{2}-8x-x^{2}=0
Subtract x^{2} from both sides.
4x^{2}-8x=0
Combine 5x^{2} and -x^{2} to get 4x^{2}.
x=\frac{-\left(-8\right)±\sqrt{\left(-8\right)^{2}}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -8 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-8\right)±8}{2\times 4}
Take the square root of \left(-8\right)^{2}.
x=\frac{8±8}{2\times 4}
The opposite of -8 is 8.
x=\frac{8±8}{8}
Multiply 2 times 4.
x=\frac{16}{8}
Now solve the equation x=\frac{8±8}{8} when ± is plus. Add 8 to 8.
x=2
Divide 16 by 8.
x=\frac{0}{8}
Now solve the equation x=\frac{8±8}{8} when ± is minus. Subtract 8 from 8.
x=0
Divide 0 by 8.
x=2 x=0
The equation is now solved.
x^{2}+16-16x+4x^{2}=\left(4-x\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4-2x\right)^{2}.
5x^{2}+16-16x=\left(4-x\right)^{2}
Combine x^{2} and 4x^{2} to get 5x^{2}.
5x^{2}+16-16x=16-8x+x^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4-x\right)^{2}.
5x^{2}+16-16x+8x=16+x^{2}
Add 8x to both sides.
5x^{2}+16-8x=16+x^{2}
Combine -16x and 8x to get -8x.
5x^{2}+16-8x-x^{2}=16
Subtract x^{2} from both sides.
4x^{2}+16-8x=16
Combine 5x^{2} and -x^{2} to get 4x^{2}.
4x^{2}-8x=16-16
Subtract 16 from both sides.
4x^{2}-8x=0
Subtract 16 from 16 to get 0.
\frac{4x^{2}-8x}{4}=\frac{0}{4}
Divide both sides by 4.
x^{2}+\left(-\frac{8}{4}\right)x=\frac{0}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-2x=\frac{0}{4}
Divide -8 by 4.
x^{2}-2x=0
Divide 0 by 4.
x^{2}-2x+1=1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
\left(x-1\right)^{2}=1
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{1}
Take the square root of both sides of the equation.
x-1=1 x-1=-1
Simplify.
x=2 x=0
Add 1 to both sides of the equation.
Examples
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Linear equation
y = 3x + 4
Arithmetic
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Matrix
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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
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Limits
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