Solve for x
x=-20
x=20
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x=10+\frac{1}{\frac{x+10}{15\left(x+10\right)}+\frac{15}{15\left(x+10\right)}}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 15 and 10+x is 15\left(x+10\right). Multiply \frac{1}{15} times \frac{x+10}{x+10}. Multiply \frac{1}{10+x} times \frac{15}{15}.
x=10+\frac{1}{\frac{x+10+15}{15\left(x+10\right)}}
Since \frac{x+10}{15\left(x+10\right)} and \frac{15}{15\left(x+10\right)} have the same denominator, add them by adding their numerators.
x=10+\frac{1}{\frac{x+25}{15\left(x+10\right)}}
Combine like terms in x+10+15.
x=10+\frac{15\left(x+10\right)}{x+25}
Variable x cannot be equal to -10 since division by zero is not defined. Divide 1 by \frac{x+25}{15\left(x+10\right)} by multiplying 1 by the reciprocal of \frac{x+25}{15\left(x+10\right)}.
x=\frac{10\left(x+25\right)}{x+25}+\frac{15\left(x+10\right)}{x+25}
To add or subtract expressions, expand them to make their denominators the same. Multiply 10 times \frac{x+25}{x+25}.
x=\frac{10\left(x+25\right)+15\left(x+10\right)}{x+25}
Since \frac{10\left(x+25\right)}{x+25} and \frac{15\left(x+10\right)}{x+25} have the same denominator, add them by adding their numerators.
x=\frac{10x+250+15x+150}{x+25}
Do the multiplications in 10\left(x+25\right)+15\left(x+10\right).
x=\frac{25x+400}{x+25}
Combine like terms in 10x+250+15x+150.
x-\frac{25x+400}{x+25}=0
Subtract \frac{25x+400}{x+25} from both sides.
\frac{x\left(x+25\right)}{x+25}-\frac{25x+400}{x+25}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{x+25}{x+25}.
\frac{x\left(x+25\right)-\left(25x+400\right)}{x+25}=0
Since \frac{x\left(x+25\right)}{x+25} and \frac{25x+400}{x+25} have the same denominator, subtract them by subtracting their numerators.
\frac{x^{2}+25x-25x-400}{x+25}=0
Do the multiplications in x\left(x+25\right)-\left(25x+400\right).
\frac{x^{2}-400}{x+25}=0
Combine like terms in x^{2}+25x-25x-400.
x^{2}-400=0
Variable x cannot be equal to -25 since division by zero is not defined. Multiply both sides of the equation by x+25.
\left(x-20\right)\left(x+20\right)=0
Consider x^{2}-400. Rewrite x^{2}-400 as x^{2}-20^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
x=20 x=-20
To find equation solutions, solve x-20=0 and x+20=0.
x=10+\frac{1}{\frac{x+10}{15\left(x+10\right)}+\frac{15}{15\left(x+10\right)}}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 15 and 10+x is 15\left(x+10\right). Multiply \frac{1}{15} times \frac{x+10}{x+10}. Multiply \frac{1}{10+x} times \frac{15}{15}.
x=10+\frac{1}{\frac{x+10+15}{15\left(x+10\right)}}
Since \frac{x+10}{15\left(x+10\right)} and \frac{15}{15\left(x+10\right)} have the same denominator, add them by adding their numerators.
x=10+\frac{1}{\frac{x+25}{15\left(x+10\right)}}
Combine like terms in x+10+15.
x=10+\frac{15\left(x+10\right)}{x+25}
Variable x cannot be equal to -10 since division by zero is not defined. Divide 1 by \frac{x+25}{15\left(x+10\right)} by multiplying 1 by the reciprocal of \frac{x+25}{15\left(x+10\right)}.
x=\frac{10\left(x+25\right)}{x+25}+\frac{15\left(x+10\right)}{x+25}
To add or subtract expressions, expand them to make their denominators the same. Multiply 10 times \frac{x+25}{x+25}.
x=\frac{10\left(x+25\right)+15\left(x+10\right)}{x+25}
Since \frac{10\left(x+25\right)}{x+25} and \frac{15\left(x+10\right)}{x+25} have the same denominator, add them by adding their numerators.
x=\frac{10x+250+15x+150}{x+25}
Do the multiplications in 10\left(x+25\right)+15\left(x+10\right).
x=\frac{25x+400}{x+25}
Combine like terms in 10x+250+15x+150.
x-\frac{25x+400}{x+25}=0
Subtract \frac{25x+400}{x+25} from both sides.
\frac{x\left(x+25\right)}{x+25}-\frac{25x+400}{x+25}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{x+25}{x+25}.
\frac{x\left(x+25\right)-\left(25x+400\right)}{x+25}=0
Since \frac{x\left(x+25\right)}{x+25} and \frac{25x+400}{x+25} have the same denominator, subtract them by subtracting their numerators.
\frac{x^{2}+25x-25x-400}{x+25}=0
Do the multiplications in x\left(x+25\right)-\left(25x+400\right).
\frac{x^{2}-400}{x+25}=0
Combine like terms in x^{2}+25x-25x-400.
x^{2}-400=0
Variable x cannot be equal to -25 since division by zero is not defined. Multiply both sides of the equation by x+25.
x^{2}=400
Add 400 to both sides. Anything plus zero gives itself.
x=20 x=-20
Take the square root of both sides of the equation.
x=10+\frac{1}{\frac{x+10}{15\left(x+10\right)}+\frac{15}{15\left(x+10\right)}}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of 15 and 10+x is 15\left(x+10\right). Multiply \frac{1}{15} times \frac{x+10}{x+10}. Multiply \frac{1}{10+x} times \frac{15}{15}.
x=10+\frac{1}{\frac{x+10+15}{15\left(x+10\right)}}
Since \frac{x+10}{15\left(x+10\right)} and \frac{15}{15\left(x+10\right)} have the same denominator, add them by adding their numerators.
x=10+\frac{1}{\frac{x+25}{15\left(x+10\right)}}
Combine like terms in x+10+15.
x=10+\frac{15\left(x+10\right)}{x+25}
Variable x cannot be equal to -10 since division by zero is not defined. Divide 1 by \frac{x+25}{15\left(x+10\right)} by multiplying 1 by the reciprocal of \frac{x+25}{15\left(x+10\right)}.
x=\frac{10\left(x+25\right)}{x+25}+\frac{15\left(x+10\right)}{x+25}
To add or subtract expressions, expand them to make their denominators the same. Multiply 10 times \frac{x+25}{x+25}.
x=\frac{10\left(x+25\right)+15\left(x+10\right)}{x+25}
Since \frac{10\left(x+25\right)}{x+25} and \frac{15\left(x+10\right)}{x+25} have the same denominator, add them by adding their numerators.
x=\frac{10x+250+15x+150}{x+25}
Do the multiplications in 10\left(x+25\right)+15\left(x+10\right).
x=\frac{25x+400}{x+25}
Combine like terms in 10x+250+15x+150.
x-\frac{25x+400}{x+25}=0
Subtract \frac{25x+400}{x+25} from both sides.
\frac{x\left(x+25\right)}{x+25}-\frac{25x+400}{x+25}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{x+25}{x+25}.
\frac{x\left(x+25\right)-\left(25x+400\right)}{x+25}=0
Since \frac{x\left(x+25\right)}{x+25} and \frac{25x+400}{x+25} have the same denominator, subtract them by subtracting their numerators.
\frac{x^{2}+25x-25x-400}{x+25}=0
Do the multiplications in x\left(x+25\right)-\left(25x+400\right).
\frac{x^{2}-400}{x+25}=0
Combine like terms in x^{2}+25x-25x-400.
x^{2}-400=0
Variable x cannot be equal to -25 since division by zero is not defined. Multiply both sides of the equation by x+25.
x=\frac{0±\sqrt{0^{2}-4\left(-400\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -400 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-400\right)}}{2}
Square 0.
x=\frac{0±\sqrt{1600}}{2}
Multiply -4 times -400.
x=\frac{0±40}{2}
Take the square root of 1600.
x=20
Now solve the equation x=\frac{0±40}{2} when ± is plus. Divide 40 by 2.
x=-20
Now solve the equation x=\frac{0±40}{2} when ± is minus. Divide -40 by 2.
x=20 x=-20
The equation is now solved.
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