I need to factor (my last post was incorrect)

Question

24x^2 + 42x + 15

Answer 1

=3(8x^2 +14x +5)
=3(2x + 1)(4x +5)

Answer 2

24x^2+42x+15=3(8x^2+14+5)
=3(8x^2+10x+4x+5)
3[2x(4x+5)+1(4x+5)]
=3(4x+5)(2x+1)

Answer 3

Please read second expression as
3(8x^2+14x+5)