what times what equals 7. If 7 is 7 then that means that 7 is also 7. So knowing that what times what equals 7.
This is called a square root. You can calculate them by typing into the web2.0calc "sqrt(X)" where X is whatever number you want. For example, sqrt(25) will give you 5, because 5*5=25.
I hope I was helpful :)