Question

Tìm x \(\in\)N biết: (11x+5)\(⋮\)(2x+31)

 

Answer 1

\(\left(11x+5\right)⋮\left(2x+31\right)\Rightarrow11\left(2x+31\right)-2\left(11x+5\right)⋮\left(2x+31\right)\)

\(\Rightarrow341-10⋮\left(2x+31\right)\Rightarrow331⋮\left(2x+31\right)\Rightarrow2x+31\inƯ\left(331\right)=\left\{1;331\right\}\)

vì \(2x+31\ge31\Rightarrow2x+31=331\Rightarrow x=150\)