# What's the difference between magnitude and pythagorean's theorem

#### bogoa

and what are the concepts of magnitudes..and how do we apply that in real life situations.

#### danskal

and what are the concepts of magnitudes..and how do we apply that in real life situations.
Magnitude just means "size" or "bigness" - so it can be used in many different situations.

Pythagoras' theorem just helps us to calculate magnitude in some situations:

If you imagine a graph with x going across and y going upwards, you can draw a line from the centre (where the axes cross at 0,0) to any point you like... for example the point 4,3 (x=4, y=3).

So if you then draw another line along the x axis to 4, and another up to the end of your line, you have drawn a triangle, and you can use pythagoras to find the length (the magnitude) of your line

magnitude2 = x2 + y2

= 42 + 32

= 16 + 9 = 25
so magnitude in this case is sqrt (25) = 5

you could use this to calculate the size of a piece of wood you would need on a gate, or something much more advanced.

hope this helps,
Michael

#### Anonymous217

Magnitude (in terms of vectors) is simply an application of the Pythagorean theorem. It's more of a subcategory than a side-by-side comparison.

#### bogoa

ah..so meaning magnitude is the application of pythagorean theorem...ahhh... makes sense..

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