Question

A certain number added to its square is 30. Find the number.

Answer 1

I got this:
5²+5=30

For the work, I just took the square I though was closest to 30, and added 5.

Hope this helps!

Answer 2

If the number is n, then n²+n=30, so n²+n-30=0=(n+6)(n-5) so there are two answers: 5 and -6.