Question

Can we write `sqrt25+sqrt16` as `sqrt41` ? Justify?

Answer 1

Nah, you can't.

Explanation:

Remember this rule the next time you add surds.
Always add surds that are the same. When I say the same, I mean the number inside the square root has the be the same. If you'd like to find out more, check out this website.
https://revisionmaths.com/gcse-maths-revision/number/surds