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Solve the equation by the method of your choice. StartFraction 1 Over x EndFraction plus StartFraction 1 Over x plus 4 EndFraction equals one half The solution set is ​{ nothing​}.

User Manro
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2 Answers

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The\ domain:\\x\\eq0\ \vedge\ x+4\\eq0\\\\D:x\in\mathbb{R}-\{-4;\ 0\}


(1)/(x)+(1)/(x+4)=(1)/(2)\\\\(x+4)/(x(x+4))+(x)/(x(x+4))=(1)/(2)\\\\(x+4+x)/(x^2+4x)=(1)/(2)\\\\(2x+4)/(x^2+4x)=(1)/(2)\ \ \ \ |cross\ multiply\\\\1(x^2+4x)=2(2x+4)\\\\x^2+4x=4x+8\ \ \ \ |-4x\\\\x^2=8\to x=\pm\sqrt8\\\\x=-√(4\cdot2)\ \vee\ x=√(4\cdot2)\\\\\boxed{x=-2\sqrt2\ \vee\ x=2\sqrt2}\\\\The\ solution\ set\ is\ \{-2\sqrt2;\ 2\sqrt2\}
User J Cracknell
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5.8k points
2 votes

Answer:


x=2√(2) and
x=2√(2)

Explanation:

The given equation is


(1)/(x)+(1)/(x+4)=(1)/(2)

We need to solve the given equation.

Taking LCM on left side.


((x+4)+x)/(x(x+4))=(1)/(2)


(2x+4)/(x^2+4x)=(1)/(2)

On cross multiplication we get


2(2x+4)=x^2+4x


4x+8=x^2+4x

Subtract 4x from both sides.


8=x^2

Taking square root on both sides.


\pm√(8)=x


\pm2√(2)=x

Therefore, solutions of the given equation are
x=2√(2) and
x=2√(2).

User Mattias Holmqvist
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