36x³-60x²+3x-5
Factor the first two terms 36x³-60x² by factoring out 12x², getting 12x²(3x-5)
So now you have:
12x²(3x-5)+3x-5
Factor the last two terms +3x-5 by factoring out 1, (I know that you don't normally factor out 1, but you need to anyway here, getting +1(3x-5)
So now you have:
12x²(3x-5)+1(3x-5)
Now you can factor out the common factor (3x-5) and the 12x² and the +1
will go in parentheses:
(3x-5)(12x²+1)
Edwin