1.Is 3x+1 a factor of 9x^2-2? How do you know?

Question

2.Where is the mistake?

t-3⟌-8t+24 Answer: -8 + 48/t-3
--8t+24
-------------------
48

Answer 1

#1. No, because 3x+1 is a factor of 9x^2-1
#2. You subtract, not add. Strange, since the -8t was properly subtracted, but not the 24.