Answer:
200
Step-by-step explanation:
Use the ratio: 20/100 = 40/X
Simplify the ratio: 1/5 = 40/X
Cross Multiply: 1X = 200
Divide both sides by 1: 1X/1 = 200/1
Simplify: X = 200
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 difference is 6 because it is what we get when we subtract 8 and 2.
Final answer: 6
Answer:
The first step should be adding 14 to both sides of the equation.
Step-by-step explanation:
14 must be added on both sides of the equation to get 13y by itself. The ultimate goal is to get y by itself if we are solving for y.
Once 14 is added on both sides, you'll get:
13y = 56.
Then 13 would be divided from both sides.
y = 4.3