I'd say what you would do is:
You can either
1. Add 15 and 18 together and then divide by 2
OR
2. Since there is a 3 number difference between 15 an 18, just add 3 to 18
3. 6/8/10 is twice the common Pythagorean Triple 3/4/5.
Answer: A. 10
4. 3/4/5 is a Pythagorean Triple because they're three natural numbers that satisfy a²+b²=c^2, here 3²+4²=5².
Answer: C
Non-zero whole numbers are called <em>natural numbers.</em>
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Sum of all interior angles of a polygon
180( n - 2) where n = number of sides in the polygon
now, if n = 19, the polygon has 19 sides, then 180( 19 - 2)
Do you know how many friends he has then you can answer the question
Answer:
20
Step-by-step explanation: add them all together
