3x2 + 36x + 81 = 3(x2 + 13x + 27)
4x2-36x+81 (2x-9)(2x-9)
3x2 + 36x + 81 = 3(x2 + 12x + 27) = 3(x + 3)(x + 9), which are its prime factors; or, if you prefer, 3x2 + 36x + 81 = (3x + 9)(x + 9), which is also accurate. You may easily verify these results by multiplying back.
(2x - 9)(2x - 9)
I'm guessing that's 36x^2 - 36x + 9 which factors to 9(2x - 1)(2x - 1)
3x2 + 36x + 81 = 3(x2 + 13x + 27)
False. It has to be either "- 24x" or "+ 36". These would factor as (3x - 4)2 and (3x - 6)2 respectively.
81.
2(5x + 7)(x - 5)
4x2-36x+81 (2x-9)(2x-9)
No, it isn't. It would be, if that "36" in the middle were "24" instead.
3x2 + 36x + 81 = 3(x2 + 12x + 27) = 3(x + 3)(x + 9), which are its prime factors; or, if you prefer, 3x2 + 36x + 81 = (3x + 9)(x + 9), which is also accurate. You may easily verify these results by multiplying back.
(x - 6)(5x - 6)
(7x2 + 9)(4x - 1)
If you mean: 9x2-36x+16 then it is not a perfect square because its discriminant is greater than zero
(2x - 9)(2x - 9)
Greatest common factor of 16x and 36x is 4x.