14 chia hết cho (2x+3)
\(\Rightarrow\left(2x+3\right)\inƯ\left(14\right)\)
\(\RightarrowƯ\left(14\right)=\left\{1;2;7;14\right\}\)
Ta có :
2x+3=1 => x= -1
2x+3=2 => x= \(\dfrac{-1}{2}\)
2x+3=7 => x= 2
2x+3=14=> x= \(\dfrac{11}{2}\)
Vì x \(\in\) N => x = 2
Vậy........