Solve for x
x=-88
x=80
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2\left(440\left(x+8\right)-440x\right)=x\left(x+8\right)
Variable x cannot be equal to any of the values -8,0 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x+8\right), the least common multiple of x\left(x+8\right),2.
2\left(440x+3520-440x\right)=x\left(x+8\right)
Use the distributive property to multiply 440 by x+8.
2\times 3520=x\left(x+8\right)
Combine 440x and -440x to get 0.
7040=x\left(x+8\right)
Multiply 2 and 3520 to get 7040.
7040=x^{2}+8x
Use the distributive property to multiply x by x+8.
x^{2}+8x=7040
Swap sides so that all variable terms are on the left hand side.
x^{2}+8x-7040=0
Subtract 7040 from both sides.
x=\frac{-8±\sqrt{8^{2}-4\left(-7040\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 8 for b, and -7040 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-8±\sqrt{64-4\left(-7040\right)}}{2}
Square 8.
x=\frac{-8±\sqrt{64+28160}}{2}
Multiply -4 times -7040.
x=\frac{-8±\sqrt{28224}}{2}
Add 64 to 28160.
x=\frac{-8±168}{2}
Take the square root of 28224.
x=\frac{160}{2}
Now solve the equation x=\frac{-8±168}{2} when ± is plus. Add -8 to 168.
x=80
Divide 160 by 2.
x=-\frac{176}{2}
Now solve the equation x=\frac{-8±168}{2} when ± is minus. Subtract 168 from -8.
x=-88
Divide -176 by 2.
x=80 x=-88
The equation is now solved.
2\left(440\left(x+8\right)-440x\right)=x\left(x+8\right)
Variable x cannot be equal to any of the values -8,0 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x+8\right), the least common multiple of x\left(x+8\right),2.
2\left(440x+3520-440x\right)=x\left(x+8\right)
Use the distributive property to multiply 440 by x+8.
2\times 3520=x\left(x+8\right)
Combine 440x and -440x to get 0.
7040=x\left(x+8\right)
Multiply 2 and 3520 to get 7040.
7040=x^{2}+8x
Use the distributive property to multiply x by x+8.
x^{2}+8x=7040
Swap sides so that all variable terms are on the left hand side.
x^{2}+8x+4^{2}=7040+4^{2}
Divide 8, the coefficient of the x term, by 2 to get 4. Then add the square of 4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+8x+16=7040+16
Square 4.
x^{2}+8x+16=7056
Add 7040 to 16.
\left(x+4\right)^{2}=7056
Factor x^{2}+8x+16. 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+4\right)^{2}}=\sqrt{7056}
Take the square root of both sides of the equation.
x+4=84 x+4=-84
Simplify.
x=80 x=-88
Subtract 4 from both sides of the equation.
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