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:
W
Step-by-step explanation:
W is the vertex, you can see the letter above the angle
Answer: y=-1/2x-4
Step-by-step explanation:
If you use point slope formula you get
y+2=-1/2(x+4)
simplify that in y=mx+b and you get
y=-1/2x-4
(-7,-5)
Step-by-step explanation:
3x-8y = 19
minus
3x + 5y = -46
0x - 13y = 65
- 13y = 65
÷-13
y = - 5
Substitute y = - 5 into one of the functions:
3x-8y = 19
-8 x - 5 = 40
3x + 40 =19
-40
3x. = - 21
÷3
x= - 7
Solution is (-7,-5)
Hope this helps!