Giải thích các bước giải:
`b) (x-5)/95 + (x-10)/90 + (x-15)/85 = (x-95)/5 + (x-90)/10 + (x-85)/15`
`=> ((x-5)/95 - 1 ) + ((x-10)/90 - 1 ) + ((x-15)/85 - 1 ) = ((x-95)/5 - 1 ) + ((x-90)/10 - 1) + ((x-85)/15 - 1)`
`=> (x-100)/95 + (x-100)/90 + (x-100)/85 = (x-100)/5 + (x-100)/10 + (x-100)/15`
`=> (x-100)/95 + (x-100)/90 + (x-100)/85 - (x-100)/5 - (x-100)/10 - (x-100)/15 = 0`
`=> (x-100)(1/95 + 1/90 + 1/85 - 1/5 - 1/10 - 1/15 ) =0`
`=> x-100 = 0`
`=> x=100`
$\\$
`c) (x-3)/15 + (x-10)/4 + (x+3)/7 = 6`
`=> ((x-3)/15 - 1 ) + ((x-10)/4 - 2) + ((x+3)/7 - 3 ) = 0`
`=> (x-18)/15 + (x-18)/4 + (x-18)/7 = 0`
`=> (x-18)(1/15 + 1/4 + 1/7)=0`
`=> x-18=0`
`=> x=18`
$\\$
`d) (x+2)/8 + (x+3)/7 + (x+4)/6 = (x+8)/2 + (x+7)/3 + (x+6)/4`
`=> ((x+2)/8 + 1 ) + ((x+3)/7 + 1 ) + ((x+4)/6 +1 ) = ((x+8)/2 + 1) + ((x+7)/3 + 1 ) + ((x+6)/4 + 1)`
`=> (x+10)/8 + (x+10)/7 + (x+10)/6 = (x+10)/2 + (x+10)/3 + (x+10)/4`
`=> (x+10)/8 + (x+10)/7 + (x+10)/6 - (x+10)/2 - (x+10)/3 - (x+10)/4 = 0`
`=> (x+10)(1/8 + 1/7 + 1/6 - 1/2 - 1/3 - 1/4)=0`
`=> x+10 = 0`
`=> x=-10`
