Solve for x
x = \frac{8}{3} = 2\frac{2}{3} \approx 2.666666667
x = \frac{7}{3} = 2\frac{1}{3} \approx 2.333333333
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-\frac{8}{9}=\left(4x-8\right)\left(x-3\right)
Use the distributive property to multiply 4 by x-2.
-\frac{8}{9}=4x^{2}-20x+24
Use the distributive property to multiply 4x-8 by x-3 and combine like terms.
4x^{2}-20x+24=-\frac{8}{9}
Swap sides so that all variable terms are on the left hand side.
4x^{2}-20x+24+\frac{8}{9}=0
Add \frac{8}{9} to both sides.
4x^{2}-20x+\frac{224}{9}=0
Add 24 and \frac{8}{9} to get \frac{224}{9}.
x=\frac{-\left(-20\right)±\sqrt{\left(-20\right)^{2}-4\times 4\times \frac{224}{9}}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -20 for b, and \frac{224}{9} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-20\right)±\sqrt{400-4\times 4\times \frac{224}{9}}}{2\times 4}
Square -20.
x=\frac{-\left(-20\right)±\sqrt{400-16\times \frac{224}{9}}}{2\times 4}
Multiply -4 times 4.
x=\frac{-\left(-20\right)±\sqrt{400-\frac{3584}{9}}}{2\times 4}
Multiply -16 times \frac{224}{9}.
x=\frac{-\left(-20\right)±\sqrt{\frac{16}{9}}}{2\times 4}
Add 400 to -\frac{3584}{9}.
x=\frac{-\left(-20\right)±\frac{4}{3}}{2\times 4}
Take the square root of \frac{16}{9}.
x=\frac{20±\frac{4}{3}}{2\times 4}
The opposite of -20 is 20.
x=\frac{20±\frac{4}{3}}{8}
Multiply 2 times 4.
x=\frac{\frac{64}{3}}{8}
Now solve the equation x=\frac{20±\frac{4}{3}}{8} when ± is plus. Add 20 to \frac{4}{3}.
x=\frac{8}{3}
Divide \frac{64}{3} by 8.
x=\frac{\frac{56}{3}}{8}
Now solve the equation x=\frac{20±\frac{4}{3}}{8} when ± is minus. Subtract \frac{4}{3} from 20.
x=\frac{7}{3}
Divide \frac{56}{3} by 8.
x=\frac{8}{3} x=\frac{7}{3}
The equation is now solved.
-\frac{8}{9}=\left(4x-8\right)\left(x-3\right)
Use the distributive property to multiply 4 by x-2.
-\frac{8}{9}=4x^{2}-20x+24
Use the distributive property to multiply 4x-8 by x-3 and combine like terms.
4x^{2}-20x+24=-\frac{8}{9}
Swap sides so that all variable terms are on the left hand side.
4x^{2}-20x=-\frac{8}{9}-24
Subtract 24 from both sides.
4x^{2}-20x=-\frac{224}{9}
Subtract 24 from -\frac{8}{9} to get -\frac{224}{9}.
\frac{4x^{2}-20x}{4}=-\frac{\frac{224}{9}}{4}
Divide both sides by 4.
x^{2}+\left(-\frac{20}{4}\right)x=-\frac{\frac{224}{9}}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-5x=-\frac{\frac{224}{9}}{4}
Divide -20 by 4.
x^{2}-5x=-\frac{56}{9}
Divide -\frac{224}{9} by 4.
x^{2}-5x+\left(-\frac{5}{2}\right)^{2}=-\frac{56}{9}+\left(-\frac{5}{2}\right)^{2}
Divide -5, the coefficient of the x term, by 2 to get -\frac{5}{2}. Then add the square of -\frac{5}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-5x+\frac{25}{4}=-\frac{56}{9}+\frac{25}{4}
Square -\frac{5}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-5x+\frac{25}{4}=\frac{1}{36}
Add -\frac{56}{9} to \frac{25}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{5}{2}\right)^{2}=\frac{1}{36}
Factor x^{2}-5x+\frac{25}{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-\frac{5}{2}\right)^{2}}=\sqrt{\frac{1}{36}}
Take the square root of both sides of the equation.
x-\frac{5}{2}=\frac{1}{6} x-\frac{5}{2}=-\frac{1}{6}
Simplify.
x=\frac{8}{3} x=\frac{7}{3}
Add \frac{5}{2} 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}