Question

 

Tìm số nguyên x thỏa mãn

A. 18

B. 4

C. - 18

D. - 4

Answer 1

\(\dfrac{12}{x}=\dfrac{-2}{3}\left(x\ne0\right).\)

\(\Leftrightarrow\dfrac{12}{x}+\dfrac{2}{3}=0.\\ \Leftrightarrow\dfrac{36+2x}{3x}=0.\\ \Rightarrow36+2x=0.\\ \Leftrightarrow2x=-36.\\ \Leftrightarrow x=-18.\\ \Rightarrow C.\)

Answer 2

\(\dfrac{12}{x}=\dfrac{-2}{3}\\ 12\times3=-2\times x\\ 36=-2\times x\\ x=36:\left(-2\right)\\ x=-18\\ \Rightarrow ChọnC\)