Question

From the same staring point, Arun and Bharat traveled in opposite directions. Each of them traveled 7 km, took a right turn and traveled 9 km further. What is the distance between Arun and Bharat ?
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Answer 1

Total distance apart in the x direction is 14km.  Total distance apart in the y direction is 18km.  So the total distance between them is found using the Pythagorean Theorem....

d^2=14^2+18^2

d^2=520

d=√520 km

d≈22.8 km (to nearest hundredth of a km)

Answer 2

Think about the two starting at 0,0 in the coordinate plane.
Then say they start travelling, one towards positive y and the other towards negative y.
They will end up at 7,0 and -7,0 after the first part.
They then turn right, so the one who was travelling towards positive y will now be travelling towards negative x, and the one travelling towards negative y will not be travelling towards positive x.
They will therefore finally end at 7,-9 and -7,9 after both parts.

Hence using pythagoras, the distance is:
sqrt((7 + 7)^2 + (9 + 9)^2) = sqrt(196 + 324) = sqrt(520)