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:
Step-by-step explanation:
∠A and ∠B are vertical => ∠A=∠B
20x+10=30x-10
20x-30x= -10-10
-10x= -20
x= -20 / -10 = 20 / 10 = 2
x=2
Good luck!
22.25 fluid ounces. Again, it may or may not be completely correct.