Solve for x
x=-\frac{\sqrt{30}}{2}-2\approx -4.738612788
x=\frac{\sqrt{30}}{2}-2\approx 0.738612788
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5-\left(2x-1\right)\times 10=\left(2x-1\right)^{2}
Variable x cannot be equal to \frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-1\right)^{2}, the least common multiple of \left(2x-1\right)^{2},2x-1.
5-\left(20x-10\right)=\left(2x-1\right)^{2}
Use the distributive property to multiply 2x-1 by 10.
5-20x+10=\left(2x-1\right)^{2}
To find the opposite of 20x-10, find the opposite of each term.
15-20x=\left(2x-1\right)^{2}
Add 5 and 10 to get 15.
15-20x=4x^{2}-4x+1
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-1\right)^{2}.
15-20x-4x^{2}=-4x+1
Subtract 4x^{2} from both sides.
15-20x-4x^{2}+4x=1
Add 4x to both sides.
15-16x-4x^{2}=1
Combine -20x and 4x to get -16x.
15-16x-4x^{2}-1=0
Subtract 1 from both sides.
14-16x-4x^{2}=0
Subtract 1 from 15 to get 14.
-4x^{2}-16x+14=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{-\left(-16\right)±\sqrt{\left(-16\right)^{2}-4\left(-4\right)\times 14}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, -16 for b, and 14 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-16\right)±\sqrt{256-4\left(-4\right)\times 14}}{2\left(-4\right)}
Square -16.
x=\frac{-\left(-16\right)±\sqrt{256+16\times 14}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{-\left(-16\right)±\sqrt{256+224}}{2\left(-4\right)}
Multiply 16 times 14.
x=\frac{-\left(-16\right)±\sqrt{480}}{2\left(-4\right)}
Add 256 to 224.
x=\frac{-\left(-16\right)±4\sqrt{30}}{2\left(-4\right)}
Take the square root of 480.
x=\frac{16±4\sqrt{30}}{2\left(-4\right)}
The opposite of -16 is 16.
x=\frac{16±4\sqrt{30}}{-8}
Multiply 2 times -4.
x=\frac{4\sqrt{30}+16}{-8}
Now solve the equation x=\frac{16±4\sqrt{30}}{-8} when ± is plus. Add 16 to 4\sqrt{30}.
x=-\frac{\sqrt{30}}{2}-2
Divide 16+4\sqrt{30} by -8.
x=\frac{16-4\sqrt{30}}{-8}
Now solve the equation x=\frac{16±4\sqrt{30}}{-8} when ± is minus. Subtract 4\sqrt{30} from 16.
x=\frac{\sqrt{30}}{2}-2
Divide 16-4\sqrt{30} by -8.
x=-\frac{\sqrt{30}}{2}-2 x=\frac{\sqrt{30}}{2}-2
The equation is now solved.
5-\left(2x-1\right)\times 10=\left(2x-1\right)^{2}
Variable x cannot be equal to \frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-1\right)^{2}, the least common multiple of \left(2x-1\right)^{2},2x-1.
5-\left(20x-10\right)=\left(2x-1\right)^{2}
Use the distributive property to multiply 2x-1 by 10.
5-20x+10=\left(2x-1\right)^{2}
To find the opposite of 20x-10, find the opposite of each term.
15-20x=\left(2x-1\right)^{2}
Add 5 and 10 to get 15.
15-20x=4x^{2}-4x+1
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2x-1\right)^{2}.
15-20x-4x^{2}=-4x+1
Subtract 4x^{2} from both sides.
15-20x-4x^{2}+4x=1
Add 4x to both sides.
15-16x-4x^{2}=1
Combine -20x and 4x to get -16x.
-16x-4x^{2}=1-15
Subtract 15 from both sides.
-16x-4x^{2}=-14
Subtract 15 from 1 to get -14.
-4x^{2}-16x=-14
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{-4x^{2}-16x}{-4}=-\frac{14}{-4}
Divide both sides by -4.
x^{2}+\left(-\frac{16}{-4}\right)x=-\frac{14}{-4}
Dividing by -4 undoes the multiplication by -4.
x^{2}+4x=-\frac{14}{-4}
Divide -16 by -4.
x^{2}+4x=\frac{7}{2}
Reduce the fraction \frac{-14}{-4} to lowest terms by extracting and canceling out 2.
x^{2}+4x+2^{2}=\frac{7}{2}+2^{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=\frac{7}{2}+4
Square 2.
x^{2}+4x+4=\frac{15}{2}
Add \frac{7}{2} to 4.
\left(x+2\right)^{2}=\frac{15}{2}
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{\frac{15}{2}}
Take the square root of both sides of the equation.
x+2=\frac{\sqrt{30}}{2} x+2=-\frac{\sqrt{30}}{2}
Simplify.
x=\frac{\sqrt{30}}{2}-2 x=-\frac{\sqrt{30}}{2}-2
Subtract 2 from 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}