The required area is totally below the x-axis in this example, so we need to use absolute value signs.

text[Area] = |int_a^bf(x) dx|

=|int_-1^2(x^2-4) dx|

=|[x^3/3 - 4x]_-1^2|

=|[(8/3-8)-(-1/3+4)]|

=|-9|

=9\ text[units]^2