Solve for x
x=60
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40\times 10+\left(\frac{1}{x}+\frac{1}{40}\right)\times 20\times 40x=40x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 40x, the least common multiple of x,40.
400+\left(\frac{1}{x}+\frac{1}{40}\right)\times 20\times 40x=40x
Multiply 40 and 10 to get 400.
400+\left(\frac{40}{40x}+\frac{x}{40x}\right)\times 20\times 40x=40x
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x and 40 is 40x. Multiply \frac{1}{x} times \frac{40}{40}. Multiply \frac{1}{40} times \frac{x}{x}.
400+\frac{40+x}{40x}\times 20\times 40x=40x
Since \frac{40}{40x} and \frac{x}{40x} have the same denominator, add them by adding their numerators.
400+\frac{40+x}{40x}\times 800x=40x
Multiply 20 and 40 to get 800.
400+\frac{\left(40+x\right)\times 800}{40x}x=40x
Express \frac{40+x}{40x}\times 800 as a single fraction.
400+\frac{20\left(x+40\right)}{x}x=40x
Cancel out 40 in both numerator and denominator.
400+\frac{20\left(x+40\right)x}{x}=40x
Express \frac{20\left(x+40\right)}{x}x as a single fraction.
\frac{400x}{x}+\frac{20\left(x+40\right)x}{x}=40x
To add or subtract expressions, expand them to make their denominators the same. Multiply 400 times \frac{x}{x}.
\frac{400x+20\left(x+40\right)x}{x}=40x
Since \frac{400x}{x} and \frac{20\left(x+40\right)x}{x} have the same denominator, add them by adding their numerators.
\frac{400x+20x^{2}+800x}{x}=40x
Do the multiplications in 400x+20\left(x+40\right)x.
\frac{1200x+20x^{2}}{x}=40x
Combine like terms in 400x+20x^{2}+800x.
\frac{1200x+20x^{2}}{x}-40x=0
Subtract 40x from both sides.
\frac{1200x+20x^{2}}{x}+\frac{-40xx}{x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -40x times \frac{x}{x}.
\frac{1200x+20x^{2}-40xx}{x}=0
Since \frac{1200x+20x^{2}}{x} and \frac{-40xx}{x} have the same denominator, add them by adding their numerators.
\frac{1200x+20x^{2}-40x^{2}}{x}=0
Do the multiplications in 1200x+20x^{2}-40xx.
\frac{1200x-20x^{2}}{x}=0
Combine like terms in 1200x+20x^{2}-40x^{2}.
1200x-20x^{2}=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x\left(1200-20x\right)=0
Factor out x.
x=0 x=60
To find equation solutions, solve x=0 and 1200-20x=0.
x=60
Variable x cannot be equal to 0.
40\times 10+\left(\frac{1}{x}+\frac{1}{40}\right)\times 20\times 40x=40x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 40x, the least common multiple of x,40.
400+\left(\frac{1}{x}+\frac{1}{40}\right)\times 20\times 40x=40x
Multiply 40 and 10 to get 400.
400+\left(\frac{40}{40x}+\frac{x}{40x}\right)\times 20\times 40x=40x
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x and 40 is 40x. Multiply \frac{1}{x} times \frac{40}{40}. Multiply \frac{1}{40} times \frac{x}{x}.
400+\frac{40+x}{40x}\times 20\times 40x=40x
Since \frac{40}{40x} and \frac{x}{40x} have the same denominator, add them by adding their numerators.
400+\frac{40+x}{40x}\times 800x=40x
Multiply 20 and 40 to get 800.
400+\frac{\left(40+x\right)\times 800}{40x}x=40x
Express \frac{40+x}{40x}\times 800 as a single fraction.
400+\frac{20\left(x+40\right)}{x}x=40x
Cancel out 40 in both numerator and denominator.
400+\frac{20\left(x+40\right)x}{x}=40x
Express \frac{20\left(x+40\right)}{x}x as a single fraction.
\frac{400x}{x}+\frac{20\left(x+40\right)x}{x}=40x
To add or subtract expressions, expand them to make their denominators the same. Multiply 400 times \frac{x}{x}.
\frac{400x+20\left(x+40\right)x}{x}=40x
Since \frac{400x}{x} and \frac{20\left(x+40\right)x}{x} have the same denominator, add them by adding their numerators.
\frac{400x+20x^{2}+800x}{x}=40x
Do the multiplications in 400x+20\left(x+40\right)x.
\frac{1200x+20x^{2}}{x}=40x
Combine like terms in 400x+20x^{2}+800x.
\frac{1200x+20x^{2}}{x}-40x=0
Subtract 40x from both sides.
\frac{1200x+20x^{2}}{x}+\frac{-40xx}{x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -40x times \frac{x}{x}.
\frac{1200x+20x^{2}-40xx}{x}=0
Since \frac{1200x+20x^{2}}{x} and \frac{-40xx}{x} have the same denominator, add them by adding their numerators.
\frac{1200x+20x^{2}-40x^{2}}{x}=0
Do the multiplications in 1200x+20x^{2}-40xx.
\frac{1200x-20x^{2}}{x}=0
Combine like terms in 1200x+20x^{2}-40x^{2}.
1200x-20x^{2}=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-20x^{2}+1200x=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-1200±\sqrt{1200^{2}}}{2\left(-20\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -20 for a, 1200 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1200±1200}{2\left(-20\right)}
Take the square root of 1200^{2}.
x=\frac{-1200±1200}{-40}
Multiply 2 times -20.
x=\frac{0}{-40}
Now solve the equation x=\frac{-1200±1200}{-40} when ± is plus. Add -1200 to 1200.
x=0
Divide 0 by -40.
x=-\frac{2400}{-40}
Now solve the equation x=\frac{-1200±1200}{-40} when ± is minus. Subtract 1200 from -1200.
x=60
Divide -2400 by -40.
x=0 x=60
The equation is now solved.
x=60
Variable x cannot be equal to 0.
40\times 10+\left(\frac{1}{x}+\frac{1}{40}\right)\times 20\times 40x=40x
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 40x, the least common multiple of x,40.
400+\left(\frac{1}{x}+\frac{1}{40}\right)\times 20\times 40x=40x
Multiply 40 and 10 to get 400.
400+\left(\frac{40}{40x}+\frac{x}{40x}\right)\times 20\times 40x=40x
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x and 40 is 40x. Multiply \frac{1}{x} times \frac{40}{40}. Multiply \frac{1}{40} times \frac{x}{x}.
400+\frac{40+x}{40x}\times 20\times 40x=40x
Since \frac{40}{40x} and \frac{x}{40x} have the same denominator, add them by adding their numerators.
400+\frac{40+x}{40x}\times 800x=40x
Multiply 20 and 40 to get 800.
400+\frac{\left(40+x\right)\times 800}{40x}x=40x
Express \frac{40+x}{40x}\times 800 as a single fraction.
400+\frac{20\left(x+40\right)}{x}x=40x
Cancel out 40 in both numerator and denominator.
400+\frac{20\left(x+40\right)x}{x}=40x
Express \frac{20\left(x+40\right)}{x}x as a single fraction.
\frac{400x}{x}+\frac{20\left(x+40\right)x}{x}=40x
To add or subtract expressions, expand them to make their denominators the same. Multiply 400 times \frac{x}{x}.
\frac{400x+20\left(x+40\right)x}{x}=40x
Since \frac{400x}{x} and \frac{20\left(x+40\right)x}{x} have the same denominator, add them by adding their numerators.
\frac{400x+20x^{2}+800x}{x}=40x
Do the multiplications in 400x+20\left(x+40\right)x.
\frac{1200x+20x^{2}}{x}=40x
Combine like terms in 400x+20x^{2}+800x.
\frac{1200x+20x^{2}}{x}-40x=0
Subtract 40x from both sides.
\frac{1200x+20x^{2}}{x}+\frac{-40xx}{x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -40x times \frac{x}{x}.
\frac{1200x+20x^{2}-40xx}{x}=0
Since \frac{1200x+20x^{2}}{x} and \frac{-40xx}{x} have the same denominator, add them by adding their numerators.
\frac{1200x+20x^{2}-40x^{2}}{x}=0
Do the multiplications in 1200x+20x^{2}-40xx.
\frac{1200x-20x^{2}}{x}=0
Combine like terms in 1200x+20x^{2}-40x^{2}.
1200x-20x^{2}=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
-20x^{2}+1200x=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-20x^{2}+1200x}{-20}=\frac{0}{-20}
Divide both sides by -20.
x^{2}+\frac{1200}{-20}x=\frac{0}{-20}
Dividing by -20 undoes the multiplication by -20.
x^{2}-60x=\frac{0}{-20}
Divide 1200 by -20.
x^{2}-60x=0
Divide 0 by -20.
x^{2}-60x+\left(-30\right)^{2}=\left(-30\right)^{2}
Divide -60, the coefficient of the x term, by 2 to get -30. Then add the square of -30 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-60x+900=900
Square -30.
\left(x-30\right)^{2}=900
Factor x^{2}-60x+900. 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-30\right)^{2}}=\sqrt{900}
Take the square root of both sides of the equation.
x-30=30 x-30=-30
Simplify.
x=60 x=0
Add 30 to both sides of the equation.
x=60
Variable x cannot be equal to 0.
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