Answer:
Answer: A real number that is not rational is called irrational. Irrational numbers include √2, π, e, and φ. The decimal expansion of an irrational number continues without repeating.
$30 because if you add 30 to those numbers it would give you the next months amount.
if we zero out f(x), namely make y = 0, we can get the roots or x-intercepts for this quadratic equation

now, the equation is in x-terms, meaning is a vertically opening parabola, so the axis of symmetry will be x = something, a vertical line.
well, we have two x-intercepts, one at -4 and another at 2, and the vertex is right half-way between those guys
-4------------(-1)------------2
so the vertex is at x=-1, namely the axis of symmetry is x = -1.
-5√x = -15
-5 -5
√x = 3
x = 9
The answer is D.