Question

1,x/9=-1/-4+1/12

2,-1/3+1/4=-1/2x

3,5/x+1+4/x+1+3/-13

Answer 1

1) \(\dfrac{x}{9}=\dfrac{-1}{-4}+\dfrac{1}{12}\)

⇔ \(\dfrac{x}{9}=\dfrac{1}{3}\)

⇔ \(x=\dfrac{9.1}{3}\)

⇔ \(x=3\)

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

⇔ \(\dfrac{-1}{12}=\dfrac{-1}{2}x\)

⇔\(x=\) \(\dfrac{-1}{12}:\dfrac{-1}{2}\)

⇔\(x=\dfrac{1}{6}\)

3)\(\dfrac{5}{x}+1+\dfrac{4}{x}+1+\dfrac{3}{-13}\)

⇔\(​​​​\dfrac{9}{x}+(2+\dfrac{3}{-13})\)

⇔ \(\dfrac{9}{x}+\dfrac{23}{13}\)

 

Answer 2

1) \(\dfrac{x}{9}=\dfrac{-1}{-4}+\dfrac{1}{12}=\dfrac{1}{3}\) \(\Rightarrow3x=9\) \(\Leftrightarrow x=3\)

2) ĐK: \(x\ne0\)

\(\dfrac{-1}{2x}=-\dfrac{1}{3}+\dfrac{1}{4}=-\dfrac{1}{12}\) \(\Rightarrow2x=12\) \(\Leftrightarrow x=6\)

3) Xem lại đề !!