Solve for x
x=2\sqrt{7}\approx 5.291502622
x=-2\sqrt{7}\approx -5.291502622
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Polynomial
5 problems similar to:
\frac { 3 - \frac { 1 } { 4 } x ^ { 2 } + x + 2 } { 2 - x } = - 1
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3-\frac{1}{4}x^{2}+x+2=-\left(-x+2\right)
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by -x+2.
5-\frac{1}{4}x^{2}+x=-\left(-x+2\right)
Add 3 and 2 to get 5.
5-\frac{1}{4}x^{2}+x=x-2
To find the opposite of -x+2, find the opposite of each term.
5-\frac{1}{4}x^{2}+x-x=-2
Subtract x from both sides.
5-\frac{1}{4}x^{2}=-2
Combine x and -x to get 0.
-\frac{1}{4}x^{2}=-2-5
Subtract 5 from both sides.
-\frac{1}{4}x^{2}=-7
Subtract 5 from -2 to get -7.
x^{2}=-7\left(-4\right)
Multiply both sides by -4, the reciprocal of -\frac{1}{4}.
x^{2}=28
Multiply -7 and -4 to get 28.
x=2\sqrt{7} x=-2\sqrt{7}
Take the square root of both sides of the equation.
3-\frac{1}{4}x^{2}+x+2=-\left(-x+2\right)
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by -x+2.
5-\frac{1}{4}x^{2}+x=-\left(-x+2\right)
Add 3 and 2 to get 5.
5-\frac{1}{4}x^{2}+x=x-2
To find the opposite of -x+2, find the opposite of each term.
5-\frac{1}{4}x^{2}+x-x=-2
Subtract x from both sides.
5-\frac{1}{4}x^{2}=-2
Combine x and -x to get 0.
5-\frac{1}{4}x^{2}+2=0
Add 2 to both sides.
7-\frac{1}{4}x^{2}=0
Add 5 and 2 to get 7.
-\frac{1}{4}x^{2}+7=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\left(-\frac{1}{4}\right)\times 7}}{2\left(-\frac{1}{4}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{1}{4} for a, 0 for b, and 7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-\frac{1}{4}\right)\times 7}}{2\left(-\frac{1}{4}\right)}
Square 0.
x=\frac{0±\sqrt{7}}{2\left(-\frac{1}{4}\right)}
Multiply -4 times -\frac{1}{4}.
x=\frac{0±\sqrt{7}}{-\frac{1}{2}}
Multiply 2 times -\frac{1}{4}.
x=-2\sqrt{7}
Now solve the equation x=\frac{0±\sqrt{7}}{-\frac{1}{2}} when ± is plus.
x=2\sqrt{7}
Now solve the equation x=\frac{0±\sqrt{7}}{-\frac{1}{2}} when ± is minus.
x=-2\sqrt{7} x=2\sqrt{7}
The equation is now solved.
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}