Andrew K. answered 04/14/14
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Hi Alicia - I think that your word problem may suffer from poor wording.
DISTANCE deals with the actual path taken - direction does not matter. For example, if you drive your car 3 miles north, then 6 miles east, you have driven a total DISTANCE of 9 miles. By the wording of the problem given, the answer should be 9 inches.
However, if we are concerned with calculating DISPLACEMENT, we are only concerned with the overall change in position from start to finish.
In this case, we want to construct a triangle showing the path taken, and calculate the distance between the start and end points.
_ _ _6_ _ _
|
3|
|
For a right triangle, we can calculate the "displacement" (hypotenuse) using the Pythagorean Theorem: a2 + b2 = c2
So the overall displacement (hypotenuse) = √(32+62)
Displacement = √(45)
= √(9) * √(5)
= 3 √(5)