Question

A ship A is moving westwards with a speed of 10 km/h and a ship B 100 km South of A, is moving northwards with aspeed of 10 km/h. The time after which the distance between them becomes the shortest is?

Answer 1

A is moving westward and B is moving towards north. The shortest distance will be the diagonal distance between A and B. They both are moving at the same speed in respective directions.

Using pythagorean triples the shortest distance should be when square root of the sums of ssquare of the distance covered by them is minimum which will be after 5 hours.

= Sqrt(50^2+50^2)

=Sqrt(2500+2500)

=Sqrt(5000)

=70.71 Kms

Answer 2

Explanation:

\;(8x+1)(x+8)

=(8x+1)(x+8)

=(8x)(x)+(8x)(8)+(1)(x)+(1)(8)

=8x2+64x+x+8

=8x2+65x+8

HOPE IT HELPS