Pythagoras was a Greek philosopher who lived over 2500 years ago. He is credited with a number of important mathematical and scientific discoveries, arguably the most significant of which has become known as Pythagoras’ Theorem.
It is an important rule that applies only to right-angled triangles. It says that ‘the square on the hypotenuse is equal to the sum of the squares on the other two sides.’
That sounds rather complicated, but it is actually quite a simple concept when we see it in a diagram:
Pythagoras’ Theorem says :
a2 + b2 = c2
So, if we know the length of two sides of a triangle and we need to calculate the third, we can use Pythagoras’ Theorem.
Let’s see if it really works using an example.
Example: A “3, 4, 5” triangle has a right angle in it.
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Let’s check if the areas are the same:
32 + 42 = 52 Calculating this becomes: 9 + 16 = 25 It works like Magic! |
However, if we know only one side length and one of the internal angles, then Pythagoras is no use to us on its own and we need to use trigonometry.
sources
https://www.skillsyouneed.com/num/trigonometry.html
https://www.mathsisfun.com/pythagoras.html