Solve for x
x=2
x=5
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x^{2}-7x+10=0
Swap sides so that all variable terms are on the left hand side.
a+b=-7 ab=10
To solve the equation, factor x^{2}-7x+10 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,-10 -2,-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 10.
-1-10=-11 -2-5=-7
Calculate the sum for each pair.
a=-5 b=-2
The solution is the pair that gives sum -7.
\left(x-5\right)\left(x-2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=5 x=2
To find equation solutions, solve x-5=0 and x-2=0.
x^{2}-7x+10=0
Swap sides so that all variable terms are on the left hand side.
a+b=-7 ab=1\times 10=10
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+10. To find a and b, set up a system to be solved.
-1,-10 -2,-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 10.
-1-10=-11 -2-5=-7
Calculate the sum for each pair.
a=-5 b=-2
The solution is the pair that gives sum -7.
\left(x^{2}-5x\right)+\left(-2x+10\right)
Rewrite x^{2}-7x+10 as \left(x^{2}-5x\right)+\left(-2x+10\right).
x\left(x-5\right)-2\left(x-5\right)
Factor out x in the first and -2 in the second group.
\left(x-5\right)\left(x-2\right)
Factor out common term x-5 by using distributive property.
x=5 x=2
To find equation solutions, solve x-5=0 and x-2=0.
x^{2}-7x+10=0
Swap sides so that all variable terms are on the left hand side.
x=\frac{-\left(-7\right)±\sqrt{\left(-7\right)^{2}-4\times 10}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -7 for b, and 10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-7\right)±\sqrt{49-4\times 10}}{2}
Square -7.
x=\frac{-\left(-7\right)±\sqrt{49-40}}{2}
Multiply -4 times 10.
x=\frac{-\left(-7\right)±\sqrt{9}}{2}
Add 49 to -40.
x=\frac{-\left(-7\right)±3}{2}
Take the square root of 9.
x=\frac{7±3}{2}
The opposite of -7 is 7.
x=\frac{10}{2}
Now solve the equation x=\frac{7±3}{2} when ± is plus. Add 7 to 3.
x=5
Divide 10 by 2.
x=\frac{4}{2}
Now solve the equation x=\frac{7±3}{2} when ± is minus. Subtract 3 from 7.
x=2
Divide 4 by 2.
x=5 x=2
The equation is now solved.
x^{2}-7x+10=0
Swap sides so that all variable terms are on the left hand side.
x^{2}-7x=-10
Subtract 10 from both sides. Anything subtracted from zero gives its negation.
x^{2}-7x+\left(-\frac{7}{2}\right)^{2}=-10+\left(-\frac{7}{2}\right)^{2}
Divide -7, the coefficient of the x term, by 2 to get -\frac{7}{2}. Then add the square of -\frac{7}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-7x+\frac{49}{4}=-10+\frac{49}{4}
Square -\frac{7}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-7x+\frac{49}{4}=\frac{9}{4}
Add -10 to \frac{49}{4}.
\left(x-\frac{7}{2}\right)^{2}=\frac{9}{4}
Factor x^{2}-7x+\frac{49}{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{7}{2}\right)^{2}}=\sqrt{\frac{9}{4}}
Take the square root of both sides of the equation.
x-\frac{7}{2}=\frac{3}{2} x-\frac{7}{2}=-\frac{3}{2}
Simplify.
x=5 x=2
Add \frac{7}{2} to both sides of the equation.
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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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