Answer:
x = 2, y = -3
Step-by-step explanation:
Add them together and get
9x + 8y - 9x - 9y = -6 + 9
-y = 3
so y = -3.
Sub it into the first equation and get
9x + 8(-3) = -6
9x - 24 = -6
9x = -6 + 24 = 18
x = 18/9 = 2
Answer: 
<u>Step-by-step explanation:</u>
f(x) = A sin (Bx - C) + D
- amplitude = |A|
- period =

- phase shift =
- vertical shift = D
<u>A</u>
amplitude of 3 is given so 3 = |A| → A = ± 3, since it is stated that this is a positive function, then A = 3
<u>B</u>
period of 6π is given so 
<u>C</u>

<u>D</u>
vertical shift of -1 is given so -1 = D
Now, substitute the values of A, B, C, and D into the formula (above):

Next, solve when x = 2π






