Question

(14+x):10=2,3
B={x apartine N / 8/x+1 apartine N

Answer 1

(14+x):10=2,3
14+x=2,3×10
14+x=23
x=23-14
x=9

B={x€N | 8/x+1 € N}
B={8/9}

Answer 2

$(14+x):10=2,3 \\ 14+x=2,3*10 \\ 14+x=23 \\ x=23-14 \\ x=9$

B={x∈ N| $\frac{8}{x}$ +1∈ N}
B= {$\frac{8}{10}$}