# distance

• Aug 5th 2010, 07:20 AM
sfspitfire23
distance
If a person moves towards west in a straight line for 6m and then to north for another 16m and then to west again for another 10m, find the distance between starting and ending point?

Can we assume that the line which connects beginning and ending points is the midpoint of the second line?
• Aug 5th 2010, 07:32 AM
Quote:

Originally Posted by sfspitfire23
If a person moves towards west in a straight line for 6m and then to north for another 16m and then to west again for another 10m, find the distance between starting and ending point?

Can we assume that the line which connects beginning and ending points is the midpoint of the second line?

No, consider why it's not safe to assume that....(the horizontal lines should be the same length).
You have perpendicular axes.
If you draw a sketch, can you use Pythagoras' Theorem?
• Aug 5th 2010, 07:43 AM
sfspitfire23
well, i then only have one side of the triangles. I need two sides for the pythagoras' theorem....
• Aug 5th 2010, 07:49 AM
Quote:

Originally Posted by sfspitfire23
well, i then only have one side of the triangles. I need two sides for the pythagoras' theorem....

You could start with the first point on the x-axis at (6,0).
Move to the origin.
Move to (0,16).
Move to (-10,16)

If you join the starting point to the endpoint,
drop a perpendicular from the endpoint to the x-axis.
Join this new point to the starting point,
you will have a right-angled triangle
with perpendicular sides 16 and 16.

You could also use trigonometry on that.