Answer:
k = -9.
Step-by-step explanation:
As the triangle is right-angled at Q, by Pythagoras:
PR^2 = PQ^2 + RQ^2
So, substituting the given data and using the distance formula between 2 points:
(7 - 1)^2 + (k - 4)^2 = (-4-4)^2 + (-3-1)^2 + (7 - (-3))^2 + (k - (-4))^2
36 + (k - 4)^2 = 64 + 16 + 100 + ( k + 4)^2
(k - 4)^2 - (k + 4)^2 = 180 - 36
k^2 - 8k + 16 - (k^2 + 8k + 16) = 144
-16k = 144
k = -9.
Answer:
A
Step-by-step explanation:
Convert the timing into hours only:
11:15 = 11.25h
9:45 = 9.75h
11:45 = 11.75h
7:45 = 7.75h
10:45 = 10.75h
To find the average, we need to find the middle of these timing:
11.25 + 9.75 + 11.75 + 7.75 + 10.75 = 51.25
51.25 ÷ 5 = 10.25h = 10:15 am
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Answer: The average time it docks is 10:15 am.
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