Hey, I have seen many multiplication problems which reverse the ones and tens digits:34*43.
Is there a trick for this?
If there is, can someone please let me know!!!!!
(10a + b)(10b + a) = 101ab + 10(a^2) + 10(b^2)
Formula is simple enough.... but so is FOILing em. I have some of them memorized since i see them so much (34*43 = 1452, 89*98 = 8722). I'd work on memorizing more useful formulas since regionals are only 5 days away.
