\(\dfrac{x+11}{89}+\dfrac{x+13}{87}=\dfrac{x+15}{85}+\dfrac{x+17}{83}\\\Leftrightarrow\left(\dfrac{x+11}{89}+1\right)+\left(\dfrac{x+13}{87}+1\right)=\left(\dfrac{x+15}{85}+1\right)+\left(\dfrac{x+17}{83}+1\right)\\ \Leftrightarrow\dfrac{x+100}{89}+\dfrac{x+100}{87}-\dfrac{x+100}{85}-\dfrac{x+100}{83}=0\\ \Leftrightarrow\left(x+100\right)\left(\dfrac{1}{89}+\dfrac{1}{87}-\dfrac{1}{85}-\dfrac{1}{83}\right)=0\\ \Leftrightarrow x+100=0\left(vì\dfrac{1}{89}+\dfrac{1}{87}-\dfrac{1}{85}-\dfrac{1}{83}\ne0\right)\\ \Leftrightarrow x=-100\)

 $\frac{x-11}{89}+\frac{x-13}{87}+\frac{x-15}{85}+\frac{x-17}{83}=4$$=>\left(\frac{x-11}{89}-1\right)+\left(\frac{x-13}{87}-1\right)+\left(\frac{x-15}{85}-1\right)+\left(\frac{x-17}{83}-1\right)=0$$=>\frac{x-100}{89}+\frac{x-100}{87}+\frac{x-100}{85}+\frac{x-100}{83}=0$$=>\left(x-100\right)\left(\frac{1}{89}+\frac{1}{87}+\frac{1}{85}+\frac{1}{83}\right)=0$=> x-100 =0 => x=100Vậy nghiệm là 100 

ta có 0=\(\frac{x-11}{89}-1+\frac{x-13}{87}-1+\frac{x-15}{85}-1+\frac{x-17}{83}-1=0\)

0=\(\frac{x-11-89}{89}+\frac{x-13-87}{87}+\frac{x-15-85}{85}+\frac{x-17-83}{83}\)

0=\(\frac{x-100}{89}+\frac{x-100}{87}+\frac{x-100}{85}+\frac{x-100}{83}\)

0=(x-100)(\(\frac{1}{89}+\frac{1}{87}+\frac{1}{85}+\frac{1}{83}\))

vì \(\frac{1}{89}+\frac{1}{87}+\frac{1}{85}+\frac{1}{83}\)khác 0      suy ra x-100=0 

                                                                                    x=100

x−11/89+x−13/87+x−15/85+x−17/83=4

=>(x−11/89−1)+(x−13/87−1)+(x−15/85−1)+(x−17/83−1)=0

=>x−100/89+x−100/87+x−100/85+x−100/83=0

=>(x−100)(1/89+1/87+1/85+1/83)=0

=> x-100 =0 

Vậy nghiệm là 100

\(\dfrac{x-13}{87}+\dfrac{x-27}{73}+\dfrac{x-67}{83}+\dfrac{x-73}{27}=4\)

<=>\(\dfrac{x-13}{87}-1+\dfrac{x-27}{73}-1+\dfrac{x-67}{83}-1+\dfrac{x-73}{27}-1=0\)

<=>\(\dfrac{x-100}{87}+\dfrac{x-100}{73}+\dfrac{x-100}{83}+\dfrac{x-100}{27}=0\)

<=>\(\left(x-100\right)\left(\dfrac{1}{87}+\dfrac{1}{73}+\dfrac{1}{83}+\dfrac{1}{27}\right)=0\)

Do \(\dfrac{1}{87}+\dfrac{1}{73}+\dfrac{1}{83}+\dfrac{1}{27}>0\)

=>x-100=0

<=>x=100

\(\dfrac{x-13}{87}+\dfrac{x-27}{73}+\dfrac{x-67}{83}+\dfrac{x-73}{27}=4\)

\(\Rightarrow\left(\dfrac{x-13}{87}-1\right)+\left(\dfrac{x-27}{73}-1\right)+\left(\dfrac{x-67}{83}-1\right)+\left(\dfrac{x-73}{27}\right)=0\)

\(\Rightarrow\dfrac{x-100}{87}+\dfrac{x-100}{73}+\dfrac{x-100}{83}+\dfrac{x-100}{27}=0\)

\(\Rightarrow\left(x-100\right)\left(\dfrac{1}{87}+\dfrac{1}{73}+\dfrac{1}{83}+\dfrac{1}{27}\right)=0\)

\(\Rightarrow x-100=0\Rightarrow x=100\)

a: \(\Leftrightarrow x+2016=0\)

hay x=-2016

b: \(\Leftrightarrow x-100=0\)

hay x=100

\(\dfrac{x+14}{86}+1+\dfrac{x+15}{85}+1+\dfrac{x+16}{84}+1+\dfrac{x+17}{83}+\dfrac{x+16}{4}=4\)

\(\dfrac{x+100}{86}+\dfrac{x+100}{85}+\dfrac{x+100}{84}+\dfrac{x+100}{83}=4-\dfrac{x+16}{4}\)

\(\left(x+100\right)\left(\dfrac{1}{86}+\dfrac{1}{85}+\dfrac{1}{84}+\dfrac{1}{83}\right)=-x\)

Mk giải đế đây rùi bạn tự giải nốt đi

À bạn có chs f ko kết pạn

1: \(\Leftrightarrow\left(\dfrac{x+1}{85}+1\right)+\left(\dfrac{x+3}{83}+1\right)=\left(\dfrac{x+5}{81}+1\right)+\left(\dfrac{x+7}{79}+1\right)\)

=>x+86=0

=>x=-86

2: \(\Leftrightarrow\left(\dfrac{x-1}{2015}+1\right)-\left(\dfrac{x+3}{2011}+1\right)=\left(\dfrac{x+7}{2007}+1\right)-\left(\dfrac{x+11}{2003}+1\right)\)

=>x+2014=0

=>x=-2014

3: \(\Leftrightarrow3\left(x+4\right)-2\left(x-3\right)=4x\)

=>4x=3x+12-2x+6

=>4x=x+18

=>3x=18

=>x=6

4: \(\Leftrightarrow15x-5\left(x+1\right)=3\left(2x+1\right)\)

=>15x-5x-5=6x+3

=>10x-5=6x+3

=>4x=8

=>x=2

5: \(\Leftrightarrow2\left(2x-7\right)+5\left(x+11\right)=-40\)

=>4x-14+5x+55=-40

=>9x+41=-40

=>x=-9

Bài 1:
\(\frac{99-x}{101}+\frac{97-x}{103}+\frac{95-x}{105}+\frac{93-x}{107}=-4\)

\(\Leftrightarrow \frac{99-x}{101}+1+\frac{97-x}{103}+1+\frac{95-x}{105}+1+\frac{93-x}{107}+1=0\)

\(\Leftrightarrow \frac{99-x+101}{101}+\frac{97-x+103}{103}+\frac{95-x+105}{105}+\frac{93-x+107}{107}=0\)

\(\Leftrightarrow \frac{200-x}{101}+\frac{200-x}{103}+\frac{200-x}{105}+\frac{200-x}{107}=0\)

\(\Leftrightarrow (200-x)\left(\frac{1}{101}+\frac{1}{103}+\frac{1}{105}+\frac{1}{107}\right)=0\)

Vì \(\frac{1}{101}+\frac{1}{103}+\frac{1}{105}+\frac{1}{107}\neq 0\) nên suy ra \(200-x=0\Rightarrow x=200\)

Bài 2:

\(\frac{x+14}{86}+\frac{x+15}{85}+\frac{x+16}{84}+\frac{x+116}{4}=0\)

\(\Leftrightarrow \frac{x+14}{86}+1+\frac{x+15}{85}+1+\frac{x+16}{84}+1+\frac{x+17}{83}+1+\frac{x+116}{4}-4=0\)

\(\Leftrightarrow \frac{x+100}{86}+\frac{x+100}{85}+\frac{x+100}{84}+\frac{x+100}{83}+\frac{x+100}{4}=0\)

\(\Leftrightarrow (x+100)\left(\frac{1}{86}+\frac{1}{85}+\frac{1}{84}+\frac{1}{83}+\frac{1}{4}\right)=0\)

Vì \(\frac{1}{86}+\frac{1}{85}+\frac{1}{84}+\frac{1}{83}+\frac{1}{4}\neq 0\). Do đó \(x+100=0\Rightarrow x=-100\)

1/

99-x/101+97-x/103+95-x/105+93-x/107

\(\Leftrightarrow\)(99-x/101+1)+(97-x/103+1)+(95-x/105+1)+(93-x/107+1)=0

\(\Leftrightarrow\)100-x/101+100-x/103+100-x/105+100-x/107=0

\(\Leftrightarrow\)(100-x)(1/101+1/103+1/105+1/107)=0

\(\Leftrightarrow\)100-x=0\(\Leftrightarrow\)

x=-100

1) \(\dfrac{11}{12}\times\dfrac{28}{13}-\dfrac{11}{12}\times\dfrac{15}{13}=\dfrac{11}{12}\times\left(\dfrac{28}{13}-\dfrac{15}{13}\right)=\dfrac{11}{12}\times\dfrac{13}{13}=\dfrac{11}{12}\times1=\dfrac{11}{12}\)

Vậy biểu thức trên có kết quả là : \(\dfrac{11}{12}\)

2) \(x+653=87\times11\)

    \(x+653=957\) 

    \(x=957-653\)

    \(x=304\)

Vậy `x = 304 `

3) \(\text{70 000 + 800 + 20 + 9}=70829\)