Math help how do i prove that if a|c and b|c then ab|c?

prove if a|c and b|c then ab|c





how do i go about doing this?? help!

Math help how do i prove that if a|c and b|c then ab|c?
This is not true, as stated.





For example, 4|12, and 6|12, but it is not true that 24|12.


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