A person moves 30 m north, then 20 m east and finally `30sqrt(2)m` south-west. This displacement from the original position is :

Options

A. 14 m south -west
B. 28 m south
C. 10m west
D. 15 m east

Answer

C

Explanation

`(x + 20)^(2)+ (30)^(2)=(30sqrt(2)^(2))`
`(x+ 20)^(2) + 30^(2) = 30^(2) xx2`
`(x+ 20)^(2) + 30^(2) = 30^(2) + 30^(2)`
`" "x + 20 = 30`
`" "x= 10`
`" "=10 "m west"`