Solve for x
x = \frac{\sqrt{313} - 3}{8} \approx 1.836475752
x=\frac{-\sqrt{313}-3}{8}\approx -2.586475752
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2\left(1-2x+4\right)-\left(4x^{2}+3x\right)=5-4\left(x+2\right)-6
To find the opposite of 2x-4, find the opposite of each term.
2\left(5-2x\right)-\left(4x^{2}+3x\right)=5-4\left(x+2\right)-6
Add 1 and 4 to get 5.
10-4x-\left(4x^{2}+3x\right)=5-4\left(x+2\right)-6
Use the distributive property to multiply 2 by 5-2x.
10-4x-4x^{2}-3x=5-4\left(x+2\right)-6
To find the opposite of 4x^{2}+3x, find the opposite of each term.
10-7x-4x^{2}=5-4\left(x+2\right)-6
Combine -4x and -3x to get -7x.
10-7x-4x^{2}=5-4x-8-6
Use the distributive property to multiply -4 by x+2.
10-7x-4x^{2}=-3-4x-6
Subtract 8 from 5 to get -3.
10-7x-4x^{2}=-9-4x
Subtract 6 from -3 to get -9.
10-7x-4x^{2}-\left(-9\right)=-4x
Subtract -9 from both sides.
10-7x-4x^{2}+9=-4x
The opposite of -9 is 9.
10-7x-4x^{2}+9+4x=0
Add 4x to both sides.
19-7x-4x^{2}+4x=0
Add 10 and 9 to get 19.
19-3x-4x^{2}=0
Combine -7x and 4x to get -3x.
-4x^{2}-3x+19=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(-3\right)±\sqrt{\left(-3\right)^{2}-4\left(-4\right)\times 19}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, -3 for b, and 19 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\left(-4\right)\times 19}}{2\left(-4\right)}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9+16\times 19}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{-\left(-3\right)±\sqrt{9+304}}{2\left(-4\right)}
Multiply 16 times 19.
x=\frac{-\left(-3\right)±\sqrt{313}}{2\left(-4\right)}
Add 9 to 304.
x=\frac{3±\sqrt{313}}{2\left(-4\right)}
The opposite of -3 is 3.
x=\frac{3±\sqrt{313}}{-8}
Multiply 2 times -4.
x=\frac{\sqrt{313}+3}{-8}
Now solve the equation x=\frac{3±\sqrt{313}}{-8} when ± is plus. Add 3 to \sqrt{313}.
x=\frac{-\sqrt{313}-3}{8}
Divide 3+\sqrt{313} by -8.
x=\frac{3-\sqrt{313}}{-8}
Now solve the equation x=\frac{3±\sqrt{313}}{-8} when ± is minus. Subtract \sqrt{313} from 3.
x=\frac{\sqrt{313}-3}{8}
Divide 3-\sqrt{313} by -8.
x=\frac{-\sqrt{313}-3}{8} x=\frac{\sqrt{313}-3}{8}
The equation is now solved.
2\left(1-2x+4\right)-\left(4x^{2}+3x\right)=5-4\left(x+2\right)-6
To find the opposite of 2x-4, find the opposite of each term.
2\left(5-2x\right)-\left(4x^{2}+3x\right)=5-4\left(x+2\right)-6
Add 1 and 4 to get 5.
10-4x-\left(4x^{2}+3x\right)=5-4\left(x+2\right)-6
Use the distributive property to multiply 2 by 5-2x.
10-4x-4x^{2}-3x=5-4\left(x+2\right)-6
To find the opposite of 4x^{2}+3x, find the opposite of each term.
10-7x-4x^{2}=5-4\left(x+2\right)-6
Combine -4x and -3x to get -7x.
10-7x-4x^{2}=5-4x-8-6
Use the distributive property to multiply -4 by x+2.
10-7x-4x^{2}=-3-4x-6
Subtract 8 from 5 to get -3.
10-7x-4x^{2}=-9-4x
Subtract 6 from -3 to get -9.
10-7x-4x^{2}+4x=-9
Add 4x to both sides.
10-3x-4x^{2}=-9
Combine -7x and 4x to get -3x.
-3x-4x^{2}=-9-10
Subtract 10 from both sides.
-3x-4x^{2}=-19
Subtract 10 from -9 to get -19.
-4x^{2}-3x=-19
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}-3x}{-4}=-\frac{19}{-4}
Divide both sides by -4.
x^{2}+\left(-\frac{3}{-4}\right)x=-\frac{19}{-4}
Dividing by -4 undoes the multiplication by -4.
x^{2}+\frac{3}{4}x=-\frac{19}{-4}
Divide -3 by -4.
x^{2}+\frac{3}{4}x=\frac{19}{4}
Divide -19 by -4.
x^{2}+\frac{3}{4}x+\left(\frac{3}{8}\right)^{2}=\frac{19}{4}+\left(\frac{3}{8}\right)^{2}
Divide \frac{3}{4}, the coefficient of the x term, by 2 to get \frac{3}{8}. Then add the square of \frac{3}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{3}{4}x+\frac{9}{64}=\frac{19}{4}+\frac{9}{64}
Square \frac{3}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{3}{4}x+\frac{9}{64}=\frac{313}{64}
Add \frac{19}{4} to \frac{9}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{3}{8}\right)^{2}=\frac{313}{64}
Factor x^{2}+\frac{3}{4}x+\frac{9}{64}. 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{3}{8}\right)^{2}}=\sqrt{\frac{313}{64}}
Take the square root of both sides of the equation.
x+\frac{3}{8}=\frac{\sqrt{313}}{8} x+\frac{3}{8}=-\frac{\sqrt{313}}{8}
Simplify.
x=\frac{\sqrt{313}-3}{8} x=\frac{-\sqrt{313}-3}{8}
Subtract \frac{3}{8} from both sides of the equation.
Examples
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{ 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}