Solve for x
x=\frac{1}{4}=0.25
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4x^{2}-2x+\frac{1}{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{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\times 4\times \frac{1}{4}}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -2 for b, and \frac{1}{4} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\times 4\times \frac{1}{4}}}{2\times 4}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4-16\times \frac{1}{4}}}{2\times 4}
Multiply -4 times 4.
x=\frac{-\left(-2\right)±\sqrt{4-4}}{2\times 4}
Multiply -16 times \frac{1}{4}.
x=\frac{-\left(-2\right)±\sqrt{0}}{2\times 4}
Add 4 to -4.
x=-\frac{-2}{2\times 4}
Take the square root of 0.
x=\frac{2}{2\times 4}
The opposite of -2 is 2.
x=\frac{2}{8}
Multiply 2 times 4.
x=\frac{1}{4}
Reduce the fraction \frac{2}{8} to lowest terms by extracting and canceling out 2.
4x^{2}-2x+\frac{1}{4}=0
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.
4x^{2}-2x+\frac{1}{4}-\frac{1}{4}=-\frac{1}{4}
Subtract \frac{1}{4} from both sides of the equation.
4x^{2}-2x=-\frac{1}{4}
Subtracting \frac{1}{4} from itself leaves 0.
\frac{4x^{2}-2x}{4}=-\frac{\frac{1}{4}}{4}
Divide both sides by 4.
x^{2}+\left(-\frac{2}{4}\right)x=-\frac{\frac{1}{4}}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-\frac{1}{2}x=-\frac{\frac{1}{4}}{4}
Reduce the fraction \frac{-2}{4} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{1}{2}x=-\frac{1}{16}
Divide -\frac{1}{4} by 4.
x^{2}-\frac{1}{2}x+\left(-\frac{1}{4}\right)^{2}=-\frac{1}{16}+\left(-\frac{1}{4}\right)^{2}
Divide -\frac{1}{2}, the coefficient of the x term, by 2 to get -\frac{1}{4}. Then add the square of -\frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{2}x+\frac{1}{16}=\frac{-1+1}{16}
Square -\frac{1}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{2}x+\frac{1}{16}=0
Add -\frac{1}{16} to \frac{1}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{4}\right)^{2}=0
Factor x^{2}-\frac{1}{2}x+\frac{1}{16}. 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-\frac{1}{4}\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-\frac{1}{4}=0 x-\frac{1}{4}=0
Simplify.
x=\frac{1}{4} x=\frac{1}{4}
Add \frac{1}{4} to both sides of the equation.
x=\frac{1}{4}
The equation is now solved. Solutions are the same.
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}