Is it necessary to have common denominators when adding or subtracting rational expressions, or does it just make it easier? The questions asks 'why is it necessary' and I just wrote 2 sentences on how it makes it easier.

Is there a way to do it without common denominators?

Question

Is it necessary to have common denominators when adding or subtracting rational expressions, or does it just make it easier? The questions asks 'why is it necessary' and I just wrote 2 sentences on  how it makes it easier. 

Is there a way to do it without common denominators?

anonymous · Answer

Using complete sentences, explain why it is necessary to have common denominators when adding or subtracting rational expressions.