Pythagoras’s Theorem

The Egyptians knew some of the principles of Pythagoras s theory, even if the Greeks who actually cracked it properly (hence the name Pythagoras was a Greek).
The Egyptians knew that if you had triangles with certain lengths for each side, you could get a right angle
That might not sound very useful - but let s remember that they didn t have precision machines back then. They didn t have protractors accurately made out of plastic.
Let s talk about the triangles. I m going to add some pictures in the next few weeks but for now - imagine a triangle with sides of 3, 4, and 5. This triangle will always have a right angle. And you could make it just with some rope and some pegs in the ground. If you measure the sides, you will get 90 degrees between the 3 side and the 4 side.
Let s look at another one: 5, 12, 13. Again, you will always get 90 degrees between the 5 and 12.
There s a bit of a rule here: 5 squared + 12 squared gives you 13 squared (use a calculator and try it out). Equally 3 squared + 4 squared gives you 5 squared (25 = 16 + 9)
What Pythagoras does is it lets us find one side of a triangle, if we know the other two sides (AND THE TRIANGLE HAS A RIGHT ANGLE).
Summary:If we know -2 sides of a triangle- that it has a right angle
We can find the other side knowing that the square of the two shorter sides is equal to the square of the longer side. We call the longer side the hypotenuse
Shortest side (squared) + middle side (squared) = hypotenuse (squared)