Solve for x
x=2
x=10
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\left(x-9\right)\left(x+2\right)-\left(x-9\right)\times 5=7
Variable x cannot be equal to any of the values -2,9 since division by zero is not defined. Multiply both sides of the equation by \left(x-9\right)\left(x+2\right), the least common multiple of x+2,x^{2}-7x-18.
x^{2}-7x-18-\left(x-9\right)\times 5=7
Use the distributive property to multiply x-9 by x+2 and combine like terms.
x^{2}-7x-18-\left(5x-45\right)=7
Use the distributive property to multiply x-9 by 5.
x^{2}-7x-18-5x+45=7
To find the opposite of 5x-45, find the opposite of each term.
x^{2}-12x-18+45=7
Combine -7x and -5x to get -12x.
x^{2}-12x+27=7
Add -18 and 45 to get 27.
x^{2}-12x+27-7=0
Subtract 7 from both sides.
x^{2}-12x+20=0
Subtract 7 from 27 to get 20.
a+b=-12 ab=20
To solve the equation, factor x^{2}-12x+20 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
-1,-20 -2,-10 -4,-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 20.
-1-20=-21 -2-10=-12 -4-5=-9
Calculate the sum for each pair.
a=-10 b=-2
The solution is the pair that gives sum -12.
\left(x-10\right)\left(x-2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=10 x=2
To find equation solutions, solve x-10=0 and x-2=0.
\left(x-9\right)\left(x+2\right)-\left(x-9\right)\times 5=7
Variable x cannot be equal to any of the values -2,9 since division by zero is not defined. Multiply both sides of the equation by \left(x-9\right)\left(x+2\right), the least common multiple of x+2,x^{2}-7x-18.
x^{2}-7x-18-\left(x-9\right)\times 5=7
Use the distributive property to multiply x-9 by x+2 and combine like terms.
x^{2}-7x-18-\left(5x-45\right)=7
Use the distributive property to multiply x-9 by 5.
x^{2}-7x-18-5x+45=7
To find the opposite of 5x-45, find the opposite of each term.
x^{2}-12x-18+45=7
Combine -7x and -5x to get -12x.
x^{2}-12x+27=7
Add -18 and 45 to get 27.
x^{2}-12x+27-7=0
Subtract 7 from both sides.
x^{2}-12x+20=0
Subtract 7 from 27 to get 20.
a+b=-12 ab=1\times 20=20
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+20. To find a and b, set up a system to be solved.
-1,-20 -2,-10 -4,-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 20.
-1-20=-21 -2-10=-12 -4-5=-9
Calculate the sum for each pair.
a=-10 b=-2
The solution is the pair that gives sum -12.
\left(x^{2}-10x\right)+\left(-2x+20\right)
Rewrite x^{2}-12x+20 as \left(x^{2}-10x\right)+\left(-2x+20\right).
x\left(x-10\right)-2\left(x-10\right)
Factor out x in the first and -2 in the second group.
\left(x-10\right)\left(x-2\right)
Factor out common term x-10 by using distributive property.
x=10 x=2
To find equation solutions, solve x-10=0 and x-2=0.
\left(x-9\right)\left(x+2\right)-\left(x-9\right)\times 5=7
Variable x cannot be equal to any of the values -2,9 since division by zero is not defined. Multiply both sides of the equation by \left(x-9\right)\left(x+2\right), the least common multiple of x+2,x^{2}-7x-18.
x^{2}-7x-18-\left(x-9\right)\times 5=7
Use the distributive property to multiply x-9 by x+2 and combine like terms.
x^{2}-7x-18-\left(5x-45\right)=7
Use the distributive property to multiply x-9 by 5.
x^{2}-7x-18-5x+45=7
To find the opposite of 5x-45, find the opposite of each term.
x^{2}-12x-18+45=7
Combine -7x and -5x to get -12x.
x^{2}-12x+27=7
Add -18 and 45 to get 27.
x^{2}-12x+27-7=0
Subtract 7 from both sides.
x^{2}-12x+20=0
Subtract 7 from 27 to get 20.
x=\frac{-\left(-12\right)±\sqrt{\left(-12\right)^{2}-4\times 20}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -12 for b, and 20 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-12\right)±\sqrt{144-4\times 20}}{2}
Square -12.
x=\frac{-\left(-12\right)±\sqrt{144-80}}{2}
Multiply -4 times 20.
x=\frac{-\left(-12\right)±\sqrt{64}}{2}
Add 144 to -80.
x=\frac{-\left(-12\right)±8}{2}
Take the square root of 64.
x=\frac{12±8}{2}
The opposite of -12 is 12.
x=\frac{20}{2}
Now solve the equation x=\frac{12±8}{2} when ± is plus. Add 12 to 8.
x=10
Divide 20 by 2.
x=\frac{4}{2}
Now solve the equation x=\frac{12±8}{2} when ± is minus. Subtract 8 from 12.
x=2
Divide 4 by 2.
x=10 x=2
The equation is now solved.
\left(x-9\right)\left(x+2\right)-\left(x-9\right)\times 5=7
Variable x cannot be equal to any of the values -2,9 since division by zero is not defined. Multiply both sides of the equation by \left(x-9\right)\left(x+2\right), the least common multiple of x+2,x^{2}-7x-18.
x^{2}-7x-18-\left(x-9\right)\times 5=7
Use the distributive property to multiply x-9 by x+2 and combine like terms.
x^{2}-7x-18-\left(5x-45\right)=7
Use the distributive property to multiply x-9 by 5.
x^{2}-7x-18-5x+45=7
To find the opposite of 5x-45, find the opposite of each term.
x^{2}-12x-18+45=7
Combine -7x and -5x to get -12x.
x^{2}-12x+27=7
Add -18 and 45 to get 27.
x^{2}-12x=7-27
Subtract 27 from both sides.
x^{2}-12x=-20
Subtract 27 from 7 to get -20.
x^{2}-12x+\left(-6\right)^{2}=-20+\left(-6\right)^{2}
Divide -12, the coefficient of the x term, by 2 to get -6. Then add the square of -6 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-12x+36=-20+36
Square -6.
x^{2}-12x+36=16
Add -20 to 36.
\left(x-6\right)^{2}=16
Factor x^{2}-12x+36. 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-6\right)^{2}}=\sqrt{16}
Take the square root of both sides of the equation.
x-6=4 x-6=-4
Simplify.
x=10 x=2
Add 6 to both sides of the equation.
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Matrix
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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
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