Given f(x) = x2 + 4x − 1 and g(x) = 5x − 7, identify (fg)(x).

 f(x) = x^2 + 4x − 1 and g(x) = 5x − 7
(fg)(x) =  (x^2 + 4x − 1)(5x − 7)
(fg)(x) = 5x^3 + 20x^2 - 5x - 7x^2 - 28x + 7
(fg)(x) =  5x^3 + 13x^2 - 33x + 7

answer is C. third choice

(fg)(x) =  5x^3 + 13x^2 - 33x + 7

No a triangle cannot be formed because when you add the two smallest number together (which would be 11) the have to be bigger than the number it is "against" ( which would be 12)

Sorry can't answer that question