Write a Pythagorean triplet whose one number is $15$.

Write a Pythagorean triplet whose one number is $63$.

Write a Pythagorean triplet whose one number is $80$.

${21}^2=441$

${201}^2=40401$

${2001}^2=4004001$

${20001}^2=4---4---1$

${200001}^2=-----------$

$9^2=81$

${99}^2=9801$

${999}^2=998001$

${9999}^2=99980001$

${99999}^2=9---8---01$

${999999}^2=9-----0----1$

$7^2=49$

${67}^2=4489$

${667}^2=444889$

${6667}^2=44448889$

${66667}^2=4----8---9$

${666667}^2=4-----8---8-$

By repeated subtraction of odd numbers starting from $1$, find whether the following number is a perfect square or not? If the number is a perfect square then find its square root.

$121$

By repeated subtraction of odd numbers starting from $1$, find whether the following number is a perfect square or not? If the number is a perfect square then find its square root.

By repeated subtraction of odd numbers starting from $1$, find whether the following number is a perfect square or not? If the number is a perfect square then find its square root.