Question

if A started walking towards north at 7 am at speed 5km/hr and B started after one hour from the same place towards east by cycle at speed 16 km/ hr . After how many hours they will be at 52 km​

Answer 1

Step-by-step explanation:

They will be at a distance of 52km between them at 11 AM

Let t = time in hrs for the walker to be 52 km from the cyclist

(t-1) = time for the cyclist to be 52km from the walker

5t = the distance walked

16(t-1) = distance cycled

, this can also be written as (16t-16)

Since the 2 people are walking towards North and East, we can use Pythagoras theorem as the angle between them is 90 degrees.

(5t)^2 + (16t-16)^2 = 52^2

25t^2+256t^2-512t+256 = 2704

281t^2 -512t-2448=0

t=4 hours. Hence, they will be at a distance of 52 km at (7+4)=11 AM