Answer: 
<u>Step-by-step explanation:</u>
Given: cos x =
, x is in Quadrant 4
Use Pythagorean Theorem to find sin x:
8² + y² = 17²
y² = 17² - 8²
y² = 289 - 64
y² = 225
y = 15
→ sin x = 
Use the double angle formula to find cos (2x):

Answer:
(6,15)
Step-by-step explanation:
The answer is in the image. We need 3.625 gallons to fill the tank.
Answer:
2 5/9 is less than 21/3; 2 5/9 < 21/3
Step-by-step explanation:
<u>Step 1: Convert 2 5/9 into an improper fraction</u>
2 5/9 = 2 * 9/9 + 5/9 = 18/9 + 5/9 = 23/9
<u>Step 2: Convert 21/3 so the denominator is 9</u>
21*3 / 3*3 = 63/9
<u>Step 3: Compare</u>
<em>23/9 < 63/9</em>
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Answer: 2 5/9 is less than 21/3; 2 5/9 < 21/3
1,400 it will be 20 qrtly making 80 a year time 5 years