Take into account, that in general, a cosine function of amplitude A, period T and vertical translation b, can be written as follow:

In the given case, you have:
A = 4
T = 3π/4
b = -3
By replacing you obtain:

Hence, the answer is:
f(x) = 4cos(8/3 x) - 3
Answer:
C
Step-by-step explanation:
Because its right
Shirts: 3 x 15.50 = 46.50
120 - 46.50 = 73.50 left to spend on shoes
73.50/32.50(cost per pair) = 2.26....so he was able to purchase 2 pairs of shoes.
36 should be added to both sides because 12/2= 6 then you square 6 to get 36 and that should be it.