You can enter this as sqrt(7), or as 7^(1/2). This is because Edfinity understands functions like sqrt (square root) and also knows that roots can be taken using exponents. Note, exponents can be entered with a ^ (caret), which is above the 6 on your keyboard. Try it. 7= You could also compute 7 on your calculator and enter the value you get. When entering decimal approximations like this, be sure to give at least five significant digits (significant digits start with the first non-zero digit). So, 2.64 will be marked wrong but 2.6457 will be marked right.