A certain natural number is not divisible by 7. Can it be divisible by 14, explain why or why not

For a number to be divisible by 14 it needs to be both divisible by 7 and 2 which are factors of 14. Every time you have a number (x) to check if it is divisible by some larger number you find the factor of that larger number and check is the x divisible by both.

Answer: it cannot be divisible by 14.