Question

if a is a factor of b and a is a factor of c then a is a factor of b and c, where a,b and c are positive integers. true or false?
**please provide proof**

Answer 1

true , deductive reasoning

Answer 2

True. I think there is a rule for this.. it is similar to if a=b and a=c, then b=c=a.

Answer 3

there are a few rules in proof but i wasn't taught properly how to use any of them!
e.g. contradiction, exhaustion, direct argument..

Answer 4

You maybe meant "... then a is a factor of bc"?