Question

(x + 1)/15 + (x+2)/7 + (x+4)/4 + 6 = -6

Answer 1

\(\dfrac{x+1}{15}+\dfrac{x+2}{7}+\dfrac{x+4}{4}+6=-6\)

\(\Leftrightarrow\dfrac{28\left(x+1\right)}{420}+\dfrac{60\left(x+2\right)}{420}+\dfrac{105\left(x+4\right)}{420}+\dfrac{6.420}{420}=\dfrac{-6.420}{420}\)

`<=> 28(x+1) +60(x+2)+105(x+4)+6.420=-6.420`

`<=> 28x+28 +60x+120 +105x+420 +2520=-2520`

`<=> 28x+28 +60x+120 +105x+420 +2520+2520=0`

`<=> 193x+5608=0`

`<=> x=-5608:193`

`<=>x= -5608/13`

Vậy pt có nghiệm `x= -5608/13`