# Question #8f515

##### 2 Answers

#### Answer:

Distance walked =

#### Explanation:

You need to know the difference between distance and displacement.

Distance is probably easier to start with. It simply means "How far did you walk altogether?"

There were 3 different stages: 50m, then 80m, then 30m

Displacement means "How far away from the starting point was I when I stopped walking?#

You should realise that walking east cancels out some of the distance to the west.

That means that your final position is the same as walking

50 m North and then 50 m West.

These lines form 2 sides of a right-angled isosceles triangle.

You need to know the length of the longest side - the slanted line which goes directly from start to finish. It is called the hypotenuse of the triangle.

To find its length, you can draw a scale diagram and measure the length of the longest side.

However, there is a method called "Pythagoras's Theorem" which you can use to calculate that length..

This length is the displacement, because you end up 70.7 m away from the starting place.

#### Answer:

Just a note about how to deal with

#### Explanation:

But

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Ok lets see if there are any squared numbers in 50 that we can also take outside the root.

But

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We can not take this any further as 2 is a prime number

So

As an approximate value this is 70.71 to 2 decimal places.