The answer is a hope it helps
Answer:
k
Step-by-step explanation:
Answer:
B
Step-by-step explanation:
Because there is three numbers
Answer:
8
Step-by-step explanation:
100 = x^2 + AC^2
17^2 = AC^2 + (21 - x)^2
289 = AC^2 + 21^2 + x^2 - 2*21*x
289 =<u> AC^2</u> + 441 +<u> x^2</u> - 42x
from 1st equation AC^2 + x^2 = 100
289 = 441 + 100 - 42x
289 = 541 - 42x
42x = 541 - 289 = 252
x = 252/42 = 6
so AC^2 = 100 - 6^2 = 100 - 36 = 64
AC = 8
Let V, be the rate in still water and let C = rate river current
If the boat is going :
upstream, its rate is V-C and if going
downstream, its rate is V+C,
But V = 5C, then
Upstream Rate: 5C - C = 4 C
Downstream rate: 5C+C = 6C
Time = distance/Rate, (or time = distance/speed) , then:
Upstream time 12/4C and
Downstream time: 12/.6C
Upstream time +downstream time:= 2h30 ' then:
12/4C + 12/.6C = 2.5 hours
3/C + 2/C = 5/2 (2.5 h = 5/2)
Reduce to same denominator :
5C = 10 and Rate of the current = 2 mi/h