Đáp án+Giải thích các bước giải:
`d)7/(x+2)=3/(x-5)`
`⇔(7.(x-5))/((x+2)(x-5))=(3.(x+2))/((x+2)(x-5))`
`⇔7(x-5)=3(x+2)`
`⇔7x-35=3x+6`
`⇔4x=41`
`⇔x=41/4`
Vậy `S=\{41/4\}`
`e)ĐKXĐ:x\ne 0;x\ne -5`
`(2x+5)/(2x)-x/(x+5)=0`
`⇔((2x+5)(x+5))/(2x(x+5))-(x.2x)/(2x(x+5))=0`
`⇒(2x+5)(x+5)-2x^2=0`
`⇔2x^2+10x+5x+25-2x^2=0`
`⇔2x^2+15x+25-2x^2=0`
`⇔15x+25=0`
`⇔15x=-25`
`⇔x=-25/15`
`⇔x=-5/3(TM)`
Vậy `S=\{-5/3\}`