Answer:
90
Step-by-step explanation:
a triangle's angles all add up to 180. take 51 and 39 away from 180 and you get 90
Answer:
rate of motorboat: b
rate of current: c
So the rate the boat travels upstream is $b - c$, and the rate it travels downstream is $b + c$
Step-by-step explanation:
d = rt
200 = (b - c)\cdot 5
200 = (b + c)\cdot 4
b - c = 40
b + c = 50
Adding these equations, we get:
2b = 90
b = 45
So
c = 50 - 45 = 5
<u>Therefore the rate of the boat is 45kph, and the rate of the current is 5kph</u>
Hope this helps :)
