Question

1/x+1/x+10=1/12

Answer 1

\(\dfrac{1}{\dfrac{x+1}{x+10}}=\dfrac{1}{12}\left(đk:x\ne1;x\ne10\right)\)

`<=> (x+10)/(x+1) =1/12 `

`<=> 12x +120 = x+1`

`<=> 12x -x = 1-120`

`<=> 11x = -119`

`<=> x=-119/11`

Vậy `S={-119/11}`

 

Answer 2

\(\Leftrightarrow\dfrac{x+10+x}{x\left(x+10\right)}=\dfrac{1}{12}\)

=>(2x+10)/(x^2+10x)=1/12

=>x^2+10x=12(2x+10)

=>x^2+10x=24x+120

=>x^2-14x-120=0

=>(x-20)(x+6)=0

=>x=20 hoặc x=-6