Solve for x
x=\frac{1}{5}=0.2
x=3
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5x^{2}-10x+3-6x=0
Subtract 6x from both sides.
5x^{2}-16x+3=0
Combine -10x and -6x to get -16x.
a+b=-16 ab=5\times 3=15
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 5x^{2}+ax+bx+3. To find a and b, set up a system to be solved.
-1,-15 -3,-5
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 15.
-1-15=-16 -3-5=-8
Calculate the sum for each pair.
a=-15 b=-1
The solution is the pair that gives sum -16.
\left(5x^{2}-15x\right)+\left(-x+3\right)
Rewrite 5x^{2}-16x+3 as \left(5x^{2}-15x\right)+\left(-x+3\right).
5x\left(x-3\right)-\left(x-3\right)
Factor out 5x in the first and -1 in the second group.
\left(x-3\right)\left(5x-1\right)
Factor out common term x-3 by using distributive property.
x=3 x=\frac{1}{5}
To find equation solutions, solve x-3=0 and 5x-1=0.
5x^{2}-10x+3-6x=0
Subtract 6x from both sides.
5x^{2}-16x+3=0
Combine -10x and -6x to get -16x.
x=\frac{-\left(-16\right)±\sqrt{\left(-16\right)^{2}-4\times 5\times 3}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, -16 for b, and 3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-16\right)±\sqrt{256-4\times 5\times 3}}{2\times 5}
Square -16.
x=\frac{-\left(-16\right)±\sqrt{256-20\times 3}}{2\times 5}
Multiply -4 times 5.
x=\frac{-\left(-16\right)±\sqrt{256-60}}{2\times 5}
Multiply -20 times 3.
x=\frac{-\left(-16\right)±\sqrt{196}}{2\times 5}
Add 256 to -60.
x=\frac{-\left(-16\right)±14}{2\times 5}
Take the square root of 196.
x=\frac{16±14}{2\times 5}
The opposite of -16 is 16.
x=\frac{16±14}{10}
Multiply 2 times 5.
x=\frac{30}{10}
Now solve the equation x=\frac{16±14}{10} when ± is plus. Add 16 to 14.
x=3
Divide 30 by 10.
x=\frac{2}{10}
Now solve the equation x=\frac{16±14}{10} when ± is minus. Subtract 14 from 16.
x=\frac{1}{5}
Reduce the fraction \frac{2}{10} to lowest terms by extracting and canceling out 2.
x=3 x=\frac{1}{5}
The equation is now solved.
5x^{2}-10x+3-6x=0
Subtract 6x from both sides.
5x^{2}-16x+3=0
Combine -10x and -6x to get -16x.
5x^{2}-16x=-3
Subtract 3 from both sides. Anything subtracted from zero gives its negation.
\frac{5x^{2}-16x}{5}=-\frac{3}{5}
Divide both sides by 5.
x^{2}-\frac{16}{5}x=-\frac{3}{5}
Dividing by 5 undoes the multiplication by 5.
x^{2}-\frac{16}{5}x+\left(-\frac{8}{5}\right)^{2}=-\frac{3}{5}+\left(-\frac{8}{5}\right)^{2}
Divide -\frac{16}{5}, the coefficient of the x term, by 2 to get -\frac{8}{5}. Then add the square of -\frac{8}{5} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{16}{5}x+\frac{64}{25}=-\frac{3}{5}+\frac{64}{25}
Square -\frac{8}{5} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{16}{5}x+\frac{64}{25}=\frac{49}{25}
Add -\frac{3}{5} to \frac{64}{25} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{8}{5}\right)^{2}=\frac{49}{25}
Factor x^{2}-\frac{16}{5}x+\frac{64}{25}. 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{8}{5}\right)^{2}}=\sqrt{\frac{49}{25}}
Take the square root of both sides of the equation.
x-\frac{8}{5}=\frac{7}{5} x-\frac{8}{5}=-\frac{7}{5}
Simplify.
x=3 x=\frac{1}{5}
Add \frac{8}{5} to 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}