# Why is the radius 'r' of this circumference equal to 1 ?

#### Ribeiro Alvo

##### New member
Given

a + b = c + d

Were 'a' and 'b' are the catheters of a rectangular triangle and 'c' the hypotenuse, 'd' is the diameter of the circumference inscribed therein.

If

a = 3
b = 4
c = 5
d = 2

Question:

Why is the radius 'r' of this circumference equal to 1 ?

#### Harry_the_cat

##### Senior Member
You've said that the diameter is 2. Therefore the radius is half of 2 which is 1. Is that what you are asking?

#### Ribeiro Alvo

##### New member
No. The question goes deeper. Maybe metaphysical.

Notice the beauty of these numbers:

1 is the radius value of the inscribed circumference
2 is the value of the diameter of the inscribed circumference
3 is the smallest catheter value
4 is the largest collet value
5 is the value of the hypotenuse
6 is the value of the triangle area
Pi is the value of the area of the entered circumference

More questions.
Why is this triangle so funny?
Can some of its properties give the value of Pi?

#### willyengland

##### New member • Harry_the_cat and Subhotosh Khan