Question

Giải các phương trình sau

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

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

3)\(\dfrac{x+4}{4}-\dfrac{x-3}{6}=\dfrac{x}{3}\)

4)\(x-\dfrac{x+1}{3}=\dfrac{2x+1}{5}\)

5) \(\dfrac{2x-7}{5}+\dfrac{x+11}{2}=-4\)

giúp em vs ạ, em đang cần gấpem c.ơn trước ạ

Answer 1

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