Solve for x
x=\sqrt{2}+5\approx 6.414213562
x=5-\sqrt{2}\approx 3.585786438
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2x^{2}-20x+48=2
Use the distributive property to multiply 2x-8 by x-6 and combine like terms.
2x^{2}-20x+48-2=0
Subtract 2 from both sides.
2x^{2}-20x+46=0
Subtract 2 from 48 to get 46.
x=\frac{-\left(-20\right)±\sqrt{\left(-20\right)^{2}-4\times 2\times 46}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -20 for b, and 46 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-20\right)±\sqrt{400-4\times 2\times 46}}{2\times 2}
Square -20.
x=\frac{-\left(-20\right)±\sqrt{400-8\times 46}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-20\right)±\sqrt{400-368}}{2\times 2}
Multiply -8 times 46.
x=\frac{-\left(-20\right)±\sqrt{32}}{2\times 2}
Add 400 to -368.
x=\frac{-\left(-20\right)±4\sqrt{2}}{2\times 2}
Take the square root of 32.
x=\frac{20±4\sqrt{2}}{2\times 2}
The opposite of -20 is 20.
x=\frac{20±4\sqrt{2}}{4}
Multiply 2 times 2.
x=\frac{4\sqrt{2}+20}{4}
Now solve the equation x=\frac{20±4\sqrt{2}}{4} when ± is plus. Add 20 to 4\sqrt{2}.
x=\sqrt{2}+5
Divide 20+4\sqrt{2} by 4.
x=\frac{20-4\sqrt{2}}{4}
Now solve the equation x=\frac{20±4\sqrt{2}}{4} when ± is minus. Subtract 4\sqrt{2} from 20.
x=5-\sqrt{2}
Divide 20-4\sqrt{2} by 4.
x=\sqrt{2}+5 x=5-\sqrt{2}
The equation is now solved.
2x^{2}-20x+48=2
Use the distributive property to multiply 2x-8 by x-6 and combine like terms.
2x^{2}-20x=2-48
Subtract 48 from both sides.
2x^{2}-20x=-46
Subtract 48 from 2 to get -46.
\frac{2x^{2}-20x}{2}=-\frac{46}{2}
Divide both sides by 2.
x^{2}+\left(-\frac{20}{2}\right)x=-\frac{46}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-10x=-\frac{46}{2}
Divide -20 by 2.
x^{2}-10x=-23
Divide -46 by 2.
x^{2}-10x+\left(-5\right)^{2}=-23+\left(-5\right)^{2}
Divide -10, the coefficient of the x term, by 2 to get -5. Then add the square of -5 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-10x+25=-23+25
Square -5.
x^{2}-10x+25=2
Add -23 to 25.
\left(x-5\right)^{2}=2
Factor x^{2}-10x+25. 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-5\right)^{2}}=\sqrt{2}
Take the square root of both sides of the equation.
x-5=\sqrt{2} x-5=-\sqrt{2}
Simplify.
x=\sqrt{2}+5 x=5-\sqrt{2}
Add 5 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}