Answer: 4
Step-by-step explanation: b =√c² - a ²
=√ 5² - 3 ²
=√16
=4
The question is an illustration of arithmetic sequence.
<em>The number of conversation for 19 people is 171</em>
<u />
<u>(a) 9 people</u>

9 represents the number of people
8 represents the number of conversation each person had
2 represents the number of people having a conversation at once (i.e 2 people at once)
<u>(b) 19 people</u>
We have:

The number of conversation is:

So, we have:




Hence, the number of conversation for 19 people is 171
Read more about arithmetic sequence at:
brainly.com/question/18109692
Since the buses travel in opposite directions, the speed at which they distance themselves is the sum of their speeds.
One bus travels at speed s.
The other bus travels at speed s + 15.
The sum of the speeds is s + s + 15 = 2s + 15
speed = distance/time
distance = speed * time
366 = (2s + 15) * 2
183 = 2s + 15
168 = 2s
s = 84
The slower bus travels at 84 km/h.
s + 15 = 84 + 15 = 99
The faster bus travels at 99 km/h.
Check:
In 2 hours, the slower bus travels 2 * 84 km = 168 km
In 2 hours, the faster bus travels 2 * 99 km = 198 km
In 2 hours, the buses are 198 km + 168 km = 366 km apart.
Our answer is correct.
Answer:
a = 5 or a = -5
Step-by-step explanation: