The question:
A cardboard figure has the shape shown below. The region is bounded on the left by the line

*x* =

*a*, on the right by the line

*x* =

*b*, above by

*f*(

*x*), and below by

*g*(

*x*). The density

*p*(

*x*) in gm/ cm2 varies only with

*x*.

Find the integral needed for the total mass of the figure. Give your answer using the form below.

I know that A =a and B=b as far as the limit of integration and that the area is (f(x)-g(x)) dx so mass is (f(x)-g(x)) dx* p(x) but im not sure how to expresses it as H(x), and anyone please help. Thank you