Solve for x
x=2\sqrt{3}+2\approx 5.464101615
x=2-2\sqrt{3}\approx -1.464101615
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\left(2\left(x-2\right)\right)^{2}-2\times \frac{16}{1}=16
Anything divided by one gives itself.
\left(2x-4\right)^{2}-2\times \frac{16}{1}=16
Use the distributive property to multiply 2 by x-2.
4x^{2}-16x+16-2\times \frac{16}{1}=16
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-4\right)^{2}.
4x^{2}-16x+16-2\times 16=16
Anything divided by one gives itself.
4x^{2}-16x+16-32=16
Multiply 2 and 16 to get 32.
4x^{2}-16x-16=16
Subtract 32 from 16 to get -16.
4x^{2}-16x-16-16=0
Subtract 16 from both sides.
4x^{2}-16x-32=0
Subtract 16 from -16 to get -32.
x=\frac{-\left(-16\right)±\sqrt{\left(-16\right)^{2}-4\times 4\left(-32\right)}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -16 for b, and -32 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-16\right)±\sqrt{256-4\times 4\left(-32\right)}}{2\times 4}
Square -16.
x=\frac{-\left(-16\right)±\sqrt{256-16\left(-32\right)}}{2\times 4}
Multiply -4 times 4.
x=\frac{-\left(-16\right)±\sqrt{256+512}}{2\times 4}
Multiply -16 times -32.
x=\frac{-\left(-16\right)±\sqrt{768}}{2\times 4}
Add 256 to 512.
x=\frac{-\left(-16\right)±16\sqrt{3}}{2\times 4}
Take the square root of 768.
x=\frac{16±16\sqrt{3}}{2\times 4}
The opposite of -16 is 16.
x=\frac{16±16\sqrt{3}}{8}
Multiply 2 times 4.
x=\frac{16\sqrt{3}+16}{8}
Now solve the equation x=\frac{16±16\sqrt{3}}{8} when ± is plus. Add 16 to 16\sqrt{3}.
x=2\sqrt{3}+2
Divide 16+16\sqrt{3} by 8.
x=\frac{16-16\sqrt{3}}{8}
Now solve the equation x=\frac{16±16\sqrt{3}}{8} when ± is minus. Subtract 16\sqrt{3} from 16.
x=2-2\sqrt{3}
Divide 16-16\sqrt{3} by 8.
x=2\sqrt{3}+2 x=2-2\sqrt{3}
The equation is now solved.
\left(2\left(x-2\right)\right)^{2}-2\times \frac{16}{1}=16
Anything divided by one gives itself.
\left(2x-4\right)^{2}-2\times \frac{16}{1}=16
Use the distributive property to multiply 2 by x-2.
4x^{2}-16x+16-2\times \frac{16}{1}=16
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-4\right)^{2}.
4x^{2}-16x+16-2\times 16=16
Anything divided by one gives itself.
4x^{2}-16x+16-32=16
Multiply 2 and 16 to get 32.
4x^{2}-16x-16=16
Subtract 32 from 16 to get -16.
4x^{2}-16x=16+16
Add 16 to both sides.
4x^{2}-16x=32
Add 16 and 16 to get 32.
\frac{4x^{2}-16x}{4}=\frac{32}{4}
Divide both sides by 4.
x^{2}+\left(-\frac{16}{4}\right)x=\frac{32}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-4x=\frac{32}{4}
Divide -16 by 4.
x^{2}-4x=8
Divide 32 by 4.
x^{2}-4x+\left(-2\right)^{2}=8+\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=8+4
Square -2.
x^{2}-4x+4=12
Add 8 to 4.
\left(x-2\right)^{2}=12
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{12}
Take the square root of both sides of the equation.
x-2=2\sqrt{3} x-2=-2\sqrt{3}
Simplify.
x=2\sqrt{3}+2 x=2-2\sqrt{3}
Add 2 to 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}