Definition:Signed Area

Definition
Consider the plane region described by a graph in the $xy$-plane.

The signed area of the region is the area such that:


 * The area of the graph on or above the $x$-axis is defined as positive


 * The area of the graph below the $x$-axis is defined as negative.

Also see

 * Definition:Definite Integral
 * Definition:Riemann Sum