Answer: see proof below
<u>Step-by-step explanation:</u>
Given: cos 330 = 
Use the Double-Angle Identity: cos 2A = 2 cos² A - 1

Proof LHS → RHS:
LHS cos 165
Double-Angle: cos (2 · 165) = 2 cos² 165 - 1
⇒ cos 330 = 2 cos² 165 - 1
⇒ 2 cos² 165 = cos 330 + 1
Given: 

Divide by 2: 

Square root: 
Scratchwork: 

Since cos 165 is in the 2nd Quadrant, the sign is NEGATIVE

LHS = RHS 
The volume for a pyramid is

, where B is the area of the base and h is the height. We are given the volume, and the base and height in terms of x. Our formula then looks like this:

. Simplifying the right side we have

. Multiply both sides by 18 to get rid of the fraction and we have

, so x = 117.575
Answer:
5.7, 6.9, 5, 7.1
Step-by-step explanation:
The absolute value of a number shows its distance from 0 on the number line, meaning it must always be positive since distance is positive. You have to perform the operations indicated on each expression to the left and match it to the correct value on the right. I got 5.7, 6.9, 5, 7.1 in order from top to bottom after adding and subtracting the numbers to the left.
the little check with the dash on top