In general, to find the area bounded by a curve and the x-axis between two given x-values, you need to separate this interval into sub-intervals where the curve is below the x-axis (there may be more than one such sub-intervals), and sub-intervals where the curve is above the x-axis. You need to integrate these sub-intervals separately. Integrating over sub-intervals where the function is negative (i.e. below the x-axis) gives you negative answers, so if you're asked for area (a positive thing), you need to flip the sign for answers where you've integrated over a place where the function is negative.
Then you need to add up all the answers to get the total area.
Then you need to add up all the answers to get the total area.