You start with 5 baseball cards and purchase 10 cards every week until you have at most 45 cards.
10 cards every week = 10 w
Start with 5 baseball cards = + 5
At Most = ≥
The function is:
(9x^2 - 36)
f(x) = ---------------------
3x + 6
You can simplify that function to a linear function for all x for which 3x + 6 ≠ 0
=> x ≠ - 2.
So, for x ≠ - 2, you can do:
(9x^2 - 36)
f(x) = --------------------- =
3x + 6
9(x^2 - 4)
f(x) = ---------------------
3(x + 2)
3(x + 2)(x - 2)
f(x) = --------------------- = 3(x - 2) = 3x - 6
(x + 2)
So, the graph is a right line that intercepts the y-axis at - 6 and the x-axis at x = 2, excluding x = -2 as the function is not defined for x = -2. That is the second graph of the second picture.
X + 4 > -15
x > -15 - 4
x > -19
The answer is: x > -19.