You can put this solution on YOUR website! x^2>=9
Plot the points 3 and -3 on a number line thus breaking
the number line into three intervals:
Check a value in each interval to determine whether the
interval values are or are not part of the solution, for
In the interval -3
Then check 0^2>=9
This is false so that interval conains no solutions.
Then check a value in each of the other two intervals.