12 = (4 * 4) - ( square root of 4 + square root of 4)
(sorry about words instead of square root symbol...cant find it on my mobile phone)
What I did was to copy and paste the "√" symbol from others posts and pasted it to where I wanted to be. There is an ASCII code (Hold <alt> down while typing the code in on numeric key pad.) for the "√" symbol but I don't know it off hand. You should be able to copy and paste on your mobile device.