you drive 2.0 km east and then 1.0 km northeast. What is your total displacement from the starting point?
break it down to horizontal and vertical components
y=1km(sin45)
x=(1km)(cos45)+2km
find displacement by basic Pythagorean theorem.
sqrt(x^2+y^2)
displacement is a vector so it has direction
tan^(-1)(y/x)