Solve for x
x=-5
x=8
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\left(x-5\right)\left(2x+4\right)=6\times 10
Variable x cannot be equal to 5 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-5\right), the least common multiple of 6,x-5.
2x^{2}-6x-20=6\times 10
Use the distributive property to multiply x-5 by 2x+4 and combine like terms.
2x^{2}-6x-20=60
Multiply 6 and 10 to get 60.
2x^{2}-6x-20-60=0
Subtract 60 from both sides.
2x^{2}-6x-80=0
Subtract 60 from -20 to get -80.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\times 2\left(-80\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -6 for b, and -80 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\times 2\left(-80\right)}}{2\times 2}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36-8\left(-80\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-6\right)±\sqrt{36+640}}{2\times 2}
Multiply -8 times -80.
x=\frac{-\left(-6\right)±\sqrt{676}}{2\times 2}
Add 36 to 640.
x=\frac{-\left(-6\right)±26}{2\times 2}
Take the square root of 676.
x=\frac{6±26}{2\times 2}
The opposite of -6 is 6.
x=\frac{6±26}{4}
Multiply 2 times 2.
x=\frac{32}{4}
Now solve the equation x=\frac{6±26}{4} when ± is plus. Add 6 to 26.
x=8
Divide 32 by 4.
x=-\frac{20}{4}
Now solve the equation x=\frac{6±26}{4} when ± is minus. Subtract 26 from 6.
x=-5
Divide -20 by 4.
x=8 x=-5
The equation is now solved.
\left(x-5\right)\left(2x+4\right)=6\times 10
Variable x cannot be equal to 5 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-5\right), the least common multiple of 6,x-5.
2x^{2}-6x-20=6\times 10
Use the distributive property to multiply x-5 by 2x+4 and combine like terms.
2x^{2}-6x-20=60
Multiply 6 and 10 to get 60.
2x^{2}-6x=60+20
Add 20 to both sides.
2x^{2}-6x=80
Add 60 and 20 to get 80.
\frac{2x^{2}-6x}{2}=\frac{80}{2}
Divide both sides by 2.
x^{2}+\left(-\frac{6}{2}\right)x=\frac{80}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-3x=\frac{80}{2}
Divide -6 by 2.
x^{2}-3x=40
Divide 80 by 2.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=40+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=40+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-3x+\frac{9}{4}=\frac{169}{4}
Add 40 to \frac{9}{4}.
\left(x-\frac{3}{2}\right)^{2}=\frac{169}{4}
Factor x^{2}-3x+\frac{9}{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{3}{2}\right)^{2}}=\sqrt{\frac{169}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{13}{2} x-\frac{3}{2}=-\frac{13}{2}
Simplify.
x=8 x=-5
Add \frac{3}{2} to both sides of the equation.
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Integration
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Limits
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