29.
[tex]f(x) = -x^2-7x-6[/tex]
As [tex]x \to \pm \infty[/tex], [tex]y \to - \infty[/tex].
This can be easily verified by looking at the graph (graph of a quadratic equation).
30.
The growth of a population is not linear, it's exponential.
31.
Exponential growth > polynomial, so [tex]y = 3^x[/tex].
35.
[tex]V(t) = 30\cdot (25)^{\frac{t}{20}}[/tex]
The question is asking V(t) for t = 40.
[tex]V(40) = 30\cdot (25)^{\frac{40}{20}} \\~\\V(40) = 30\cdot 25^2 \\~\\V(40) = 30\cdot 625 \\~\\V(40) = 18750[/tex]
36.
The point of symmetry of a quadratic equation [tex]y = ax^2+bx+c[/tex] is at its vertice:
[tex]V_x = \dfrac{-b}{2a}[/tex]
[tex]V_x = \dfrac{6}{2}[/tex]
[tex]V_x = 3[/tex]
The line is x= 3.
