\(5x+1\text{⋮}2x+3\)
\(\text{⇒}2\left(5x+1\right)\text{⋮}2x+3\)
\(\text{⇒}10x+2\text{⋮}2x+3\)
\(\text{⇒}10x+15-13\text{⋮}2x+3\)
\(\text{⇒}5\left(2x+3\right)-13\text{⋮}2x+3\)
\(\text{⇒}13\text{⋮}2x+3\)
\(\text{⇒}2x+3\text{∈}Ư\left(13\right)=\left\{13;-13;1;-1\right\}\)
\(\text{⇒}2x\text{∈ }\left\{10;-16;-2;-4\right\}\)
\(\text{⇒}x\text{∈}\left\{5;-8;-1;-2\right\}\)
Vậy \(x\text{∈}\left\{5;8;-1;-2\right\}\)
1-1-2-3-4-5-6-7-8-9
x=-1/5 (Xin lỗi mình không thể hiển thị lời giải được ạ)