Step-by-step explanation:
I think we have to find the factors so
3x2 + 42x + 105
First we will multiply 105 by 3 = 315 then find factors of 315 which may add or subtract = 42
So 45 and 7
3x2 + 45x - 7x + 105
3x( x + 15) - 7(x - 15)
(3x - 7) and ( x - 15) are the factors
There is a problem please recheck the question