Question

Write a Pythagorean triplet for $20,21$

Answer 1

A Pythagorean triple consist of three positive integers $a,b$ and $c$ so that $a^2+b^2=c^2$. If $(a,b,c)$ is a Pythagorean triple, so is $(ka,kb,kc)$ for any positive integer $k$. A primitive Pythagorean triple is one in which $a,b$ and $c$ are co-prim.

Here $a=20,b=21\therefore c=29$ i.e $a^2+b^2=c^2$

${20}^2+{21}^2={29}^2$

$\therefore (20,21,29)$