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37 votes
Solve the equation-

(5)/(x - 3) - (4)/(x + 4) = (1)/(x)


User Escher
by
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2 Answers

29 votes
29 votes

Hello studentUnion!


\huge \boxed{\mathfrak{Question} \downarrow}

Solve the equation-


(5)/(x - 3) - (4)/(x + 4) = (1)/(x) \\


\large \boxed{\mathfrak{Answer \: with \: Explanation} \downarrow}


(5)/(x - 3) - (4)/(x + 4) = (1)/(x) \\

Let's multiply both the sides of the equation by x (x - 3) & (x + 4) which is the LCM of (x - 3), (x + 4) & x. We can't solve it directly without taking the LCM first as the denominators are not equal to each other. Then do cross multiplication. After all these steps, you'll get an equation as..


x\left(x+4\right)* 5-x\left(x-3\right)* 4=\left(x-3\right)\left(x+4\right) \\

Now, use the distributive property & simplify it.


x\left(x+4\right)* 5-x\left(x-3\right)* 4=\left(x-3\right)\left(x+4\right) \\ \left(x^(2)+4x\right)* 5-x\left(x-3\right)* 4=\left(x-3\right)\left(x+4\right) \\ 5x^(2)+20x-x\left(x-3\right)* 4=\left(x-3\right)\left(x+4\right) \\ 5x^(2)+20x-\left(x^(2)-3x\right)* 4=\left(x-3\right)\left(x+4\right) \\ 5x^(2)+20x-\left(4x^(2)-12x\right)=\left(x-3\right)\left(x+4\right) \\ 5x^(2)+20x-4x^(2)+12x=\left(x-3\right)\left(x+4\right) \\ x^(2)+20x+12x=\left(x-3\right)\left(x+4\right) \\ x^(2)+32x=\left(x-3\right)\left(x+4\right) \\ x^(2)+32x=x^(2)+x-12 \\ x^(2)+32x-x^(2)=x-12 \\ 32x=x-12 \\ 32x-x=-12 \\ 31x=-12 \\ \boxed{ \boxed{ \bf \: x=-(12)/(31) }}

  • The value of x is -12/31.

__________________

Hope it'll help you!

ℓu¢αzz ッ

User Jram
by
2.3k points
20 votes
20 votes

Answer:


(5)/(x-3) -(4)/(x+4) =(1)/(x)


(5(x+4)-4(x-3))/((x-3)(x+4)) =(1)/(x) \\


(5x+20-4x+12)/((x-3)(x+4)) =(1)/(x)


(x+32)/((x-3)(x+4)) =(1)/(x)

Use Cross multiplication


x(x+32)=(x-3)(x+4)


x^(2) +32x = x^(2) +4x-3x-12


x^(2) +32x=x^(2) +x-12


x^(2) +32x-x^(2) -x=-12


31x = -12


(31x)/(31) =(-12)/(31) \\x = (-12)/(31)

Hope this helps you.

Let me know if you have any other questions :-)

User Vladimir Ignatov
by
3.0k points