Solve for x
x = \frac{7}{4} = 1\frac{3}{4} = 1.75
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\left(x-2\right)\left(x-5\right)+\left(x-5\right)\left(x-2\right)\times 3=5-x
Variable x cannot be equal to any of the values 2,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x-2\right), the least common multiple of x-5,2-x.
x^{2}-7x+10+\left(x-5\right)\left(x-2\right)\times 3=5-x
Use the distributive property to multiply x-2 by x-5 and combine like terms.
x^{2}-7x+10+\left(x^{2}-7x+10\right)\times 3=5-x
Use the distributive property to multiply x-5 by x-2 and combine like terms.
x^{2}-7x+10+3x^{2}-21x+30=5-x
Use the distributive property to multiply x^{2}-7x+10 by 3.
4x^{2}-7x+10-21x+30=5-x
Combine x^{2} and 3x^{2} to get 4x^{2}.
4x^{2}-28x+10+30=5-x
Combine -7x and -21x to get -28x.
4x^{2}-28x+40=5-x
Add 10 and 30 to get 40.
4x^{2}-28x+40-5=-x
Subtract 5 from both sides.
4x^{2}-28x+35=-x
Subtract 5 from 40 to get 35.
4x^{2}-28x+35+x=0
Add x to both sides.
4x^{2}-27x+35=0
Combine -28x and x to get -27x.
x=\frac{-\left(-27\right)±\sqrt{\left(-27\right)^{2}-4\times 4\times 35}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -27 for b, and 35 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-27\right)±\sqrt{729-4\times 4\times 35}}{2\times 4}
Square -27.
x=\frac{-\left(-27\right)±\sqrt{729-16\times 35}}{2\times 4}
Multiply -4 times 4.
x=\frac{-\left(-27\right)±\sqrt{729-560}}{2\times 4}
Multiply -16 times 35.
x=\frac{-\left(-27\right)±\sqrt{169}}{2\times 4}
Add 729 to -560.
x=\frac{-\left(-27\right)±13}{2\times 4}
Take the square root of 169.
x=\frac{27±13}{2\times 4}
The opposite of -27 is 27.
x=\frac{27±13}{8}
Multiply 2 times 4.
x=\frac{40}{8}
Now solve the equation x=\frac{27±13}{8} when ± is plus. Add 27 to 13.
x=5
Divide 40 by 8.
x=\frac{14}{8}
Now solve the equation x=\frac{27±13}{8} when ± is minus. Subtract 13 from 27.
x=\frac{7}{4}
Reduce the fraction \frac{14}{8} to lowest terms by extracting and canceling out 2.
x=5 x=\frac{7}{4}
The equation is now solved.
x=\frac{7}{4}
Variable x cannot be equal to 5.
\left(x-2\right)\left(x-5\right)+\left(x-5\right)\left(x-2\right)\times 3=5-x
Variable x cannot be equal to any of the values 2,5 since division by zero is not defined. Multiply both sides of the equation by \left(x-5\right)\left(x-2\right), the least common multiple of x-5,2-x.
x^{2}-7x+10+\left(x-5\right)\left(x-2\right)\times 3=5-x
Use the distributive property to multiply x-2 by x-5 and combine like terms.
x^{2}-7x+10+\left(x^{2}-7x+10\right)\times 3=5-x
Use the distributive property to multiply x-5 by x-2 and combine like terms.
x^{2}-7x+10+3x^{2}-21x+30=5-x
Use the distributive property to multiply x^{2}-7x+10 by 3.
4x^{2}-7x+10-21x+30=5-x
Combine x^{2} and 3x^{2} to get 4x^{2}.
4x^{2}-28x+10+30=5-x
Combine -7x and -21x to get -28x.
4x^{2}-28x+40=5-x
Add 10 and 30 to get 40.
4x^{2}-28x+40+x=5
Add x to both sides.
4x^{2}-27x+40=5
Combine -28x and x to get -27x.
4x^{2}-27x=5-40
Subtract 40 from both sides.
4x^{2}-27x=-35
Subtract 40 from 5 to get -35.
\frac{4x^{2}-27x}{4}=-\frac{35}{4}
Divide both sides by 4.
x^{2}-\frac{27}{4}x=-\frac{35}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-\frac{27}{4}x+\left(-\frac{27}{8}\right)^{2}=-\frac{35}{4}+\left(-\frac{27}{8}\right)^{2}
Divide -\frac{27}{4}, the coefficient of the x term, by 2 to get -\frac{27}{8}. Then add the square of -\frac{27}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{27}{4}x+\frac{729}{64}=-\frac{35}{4}+\frac{729}{64}
Square -\frac{27}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{27}{4}x+\frac{729}{64}=\frac{169}{64}
Add -\frac{35}{4} to \frac{729}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{27}{8}\right)^{2}=\frac{169}{64}
Factor x^{2}-\frac{27}{4}x+\frac{729}{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{27}{8}\right)^{2}}=\sqrt{\frac{169}{64}}
Take the square root of both sides of the equation.
x-\frac{27}{8}=\frac{13}{8} x-\frac{27}{8}=-\frac{13}{8}
Simplify.
x=5 x=\frac{7}{4}
Add \frac{27}{8} to both sides of the equation.
x=\frac{7}{4}
Variable x cannot be equal to 5.
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Differentiation
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Integration
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Limits
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