#YES
No doubts whatsoever here. At the very least, citing a high-school level textbook is an easy way of supporting the answer, and of proving that the answer is high-school level.
Supporting this kind of answers with references has a low cost to the answerer. On the other hand, answers that dismiss a claim because "it's obvious", are not beneficial to the OP or the site at all.
Let's invest 5 minutes and reference such answers!