Đáp án:
Giải thích các bước giải:
`a,22/7:(11-x)+2/3=7/5 `
`=>22/7:(11-x)=7/5-2/3`
`=>22/7:(11-x)=11/15 `
`=>11-x=22/7:11/15`
`=>11-x=30/7`
`=>x=11-30/7`
`=>x=47/7`
`b)(x+1)+(x+2)+(x+3)+...+(x+100)=5550`
`=>x+1+x+2+x+3+...+x+100=5550`
`=>100x+5050=5550`
`=>100x=5550-5050`
`=>100x=500`
`=>x=5`