Solve for x
x=\frac{1}{4}=0.25
x=2
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3x^{2}-x-10+\left(x-2\right)\left(x-6\right)=0
Use the distributive property to multiply x-2 by 3x+5 and combine like terms.
3x^{2}-x-10+x^{2}-8x+12=0
Use the distributive property to multiply x-2 by x-6 and combine like terms.
4x^{2}-x-10-8x+12=0
Combine 3x^{2} and x^{2} to get 4x^{2}.
4x^{2}-9x-10+12=0
Combine -x and -8x to get -9x.
4x^{2}-9x+2=0
Add -10 and 12 to get 2.
a+b=-9 ab=4\times 2=8
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 4x^{2}+ax+bx+2. To find a and b, set up a system to be solved.
-1,-8 -2,-4
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 8.
-1-8=-9 -2-4=-6
Calculate the sum for each pair.
a=-8 b=-1
The solution is the pair that gives sum -9.
\left(4x^{2}-8x\right)+\left(-x+2\right)
Rewrite 4x^{2}-9x+2 as \left(4x^{2}-8x\right)+\left(-x+2\right).
4x\left(x-2\right)-\left(x-2\right)
Factor out 4x in the first and -1 in the second group.
\left(x-2\right)\left(4x-1\right)
Factor out common term x-2 by using distributive property.
x=2 x=\frac{1}{4}
To find equation solutions, solve x-2=0 and 4x-1=0.
3x^{2}-x-10+\left(x-2\right)\left(x-6\right)=0
Use the distributive property to multiply x-2 by 3x+5 and combine like terms.
3x^{2}-x-10+x^{2}-8x+12=0
Use the distributive property to multiply x-2 by x-6 and combine like terms.
4x^{2}-x-10-8x+12=0
Combine 3x^{2} and x^{2} to get 4x^{2}.
4x^{2}-9x-10+12=0
Combine -x and -8x to get -9x.
4x^{2}-9x+2=0
Add -10 and 12 to get 2.
x=\frac{-\left(-9\right)±\sqrt{\left(-9\right)^{2}-4\times 4\times 2}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -9 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-9\right)±\sqrt{81-4\times 4\times 2}}{2\times 4}
Square -9.
x=\frac{-\left(-9\right)±\sqrt{81-16\times 2}}{2\times 4}
Multiply -4 times 4.
x=\frac{-\left(-9\right)±\sqrt{81-32}}{2\times 4}
Multiply -16 times 2.
x=\frac{-\left(-9\right)±\sqrt{49}}{2\times 4}
Add 81 to -32.
x=\frac{-\left(-9\right)±7}{2\times 4}
Take the square root of 49.
x=\frac{9±7}{2\times 4}
The opposite of -9 is 9.
x=\frac{9±7}{8}
Multiply 2 times 4.
x=\frac{16}{8}
Now solve the equation x=\frac{9±7}{8} when ± is plus. Add 9 to 7.
x=2
Divide 16 by 8.
x=\frac{2}{8}
Now solve the equation x=\frac{9±7}{8} when ± is minus. Subtract 7 from 9.
x=\frac{1}{4}
Reduce the fraction \frac{2}{8} to lowest terms by extracting and canceling out 2.
x=2 x=\frac{1}{4}
The equation is now solved.
3x^{2}-x-10+\left(x-2\right)\left(x-6\right)=0
Use the distributive property to multiply x-2 by 3x+5 and combine like terms.
3x^{2}-x-10+x^{2}-8x+12=0
Use the distributive property to multiply x-2 by x-6 and combine like terms.
4x^{2}-x-10-8x+12=0
Combine 3x^{2} and x^{2} to get 4x^{2}.
4x^{2}-9x-10+12=0
Combine -x and -8x to get -9x.
4x^{2}-9x+2=0
Add -10 and 12 to get 2.
4x^{2}-9x=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
\frac{4x^{2}-9x}{4}=-\frac{2}{4}
Divide both sides by 4.
x^{2}-\frac{9}{4}x=-\frac{2}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-\frac{9}{4}x=-\frac{1}{2}
Reduce the fraction \frac{-2}{4} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{9}{4}x+\left(-\frac{9}{8}\right)^{2}=-\frac{1}{2}+\left(-\frac{9}{8}\right)^{2}
Divide -\frac{9}{4}, the coefficient of the x term, by 2 to get -\frac{9}{8}. Then add the square of -\frac{9}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{9}{4}x+\frac{81}{64}=-\frac{1}{2}+\frac{81}{64}
Square -\frac{9}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{9}{4}x+\frac{81}{64}=\frac{49}{64}
Add -\frac{1}{2} to \frac{81}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{9}{8}\right)^{2}=\frac{49}{64}
Factor x^{2}-\frac{9}{4}x+\frac{81}{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{9}{8}\right)^{2}}=\sqrt{\frac{49}{64}}
Take the square root of both sides of the equation.
x-\frac{9}{8}=\frac{7}{8} x-\frac{9}{8}=-\frac{7}{8}
Simplify.
x=2 x=\frac{1}{4}
Add \frac{9}{8} 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}