For class 10th students
Find the distance between the points A (a,b) and B (b,a) if a-b = 4.
Note : Answer is in decimal like 7.78
Only 2 digit after decimal
Hint try to find root
The answer is 5.64.
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2 solutions
Very good #claps#whistles for Abhiram
The distance between points A and B is ( b − a ) 2 + ( a − b ) 2 = 2 ( a − b ) 2 We are given a − b = 4 , so the distance is 2 ( 1 6 ) = 4 2 ≈ 5 . 6 4
Since the problem asks for only 2 digits after the decimal, it was actually a 1-second calculation knowing that 2 ≈ 1 . 4 1 . It sometimes pays to learn simple approximations.
Calculate it using a scientific calculator. The answer is actually 5.65685..., which should be rounded to 5.66 as the question states.
Why only for 10th? 8th graders can also solve it.