We sill start with a simple example.
We will find the area under the horizontal line y = 1 from
x = 0 to x = 5.
We know that the answer is 5.
This is the same as
We'll need to use the "Area" tool, so click on the "Area"
button in the left column.
You should get a window named "Estimate Area Under Curve".
Graph the curve y = 1 by entering a 1 in the "y ="
text field and pressing the "Graph Your Equation" button.
Now we will get a geometric shape, resize it to fit between the curve and
the xaxis, and then calculate the area of the shape.
 Click once on the blue rectangle in the upper right hand corner of
the graphing area.
A rectangle will drop out and land on the xaxis.
 You want to move and resize the rectangle so that it fits (as closely
as possible) the area enclosed by the xaxis, yaxis, the line
x = 5, and the line y = 1.
You move the rectangle by clicking and dragging inside the rectangle's
boundaries.
You resize the rectangle by clicking and dragging on a corner
of the rectangle.
 Once you have the rectangle sized and positioned correctly, then
press the "Calculate Area" button.
You should get an answer that is close to 5.
Note that any shape that is fully in the graphing window will be added into
the area calculation.
You can click and drag extraneous shapes off the screen so that they are not
part of the area calculation.
Next: Follow the "A Second Line" link.
