A roller coaster moves 4.2 m horizontally, then travels 6.9 m at an angle of 30º above the horizontal. What is the resultant displacement from its starting point?

Answer 1

starting at (0,0), it moves 4.2m

now at (4.2,0) it moves 6.9m at 30º, or (6.9 cos 30º, 6.9 sin 30º) = (5.98,3.45), ending up at (10.18,3.45)