The code is not working because you are not assigning the value of
math.sqrt(100) to a variable. To get a useable value, assign it to a variable like
my_variable = math.sqrt(100). To print it, do
print math.sqrt(100) or
The only thing that your code does is import the
math module then run the
sqrt() function. The reason there is nothing in IDLE is because your program is not written to have any output.