`(3/4x-8/13).(2,5+ -7/5÷x)=0`
`3/4x-8/13=0` hoặc `2,5+ -7/5÷x=0`
$\text{* $\dfrac{3}{4}$x - $\dfrac{8}{13}$ = 0.}$
`⇒3/4x=0+8/13.`
`⇒3/4x=8/13.`
`⇒x=8/13÷3/4.`
`⇒x=8/13. 4/3.`
`⇒x=32/39.`
$\text{* 2,5 + $\dfrac{-7}{5}$ ÷ x= 0.}$
`⇒-7/5÷x=0-2,5`
`⇒-7/5÷x=-2,5`
`⇒x=-7/5÷-2,5`
`⇒x=-7/5÷-25/10`
`⇒x=-7/5. -10/25`
`⇒x=14/25`
$\text{Vậy x = $\dfrac{32}{39}$ hoặc x = $\dfrac{14}{25}$.}$
