Working with the graph: add a line as second graph

Adding a line as a second graph is useful when you study a relationship between function y = f(x) and line (function) y = ax + b. The app provides tools to do that:

1) Add/Remove a line
2) Change a line by moving and/or rotating a line
3) Shows intersection points between the two graphs
4) Solve the equation f(x) = ax + b and output the results
5) Attach the line & intersections to the graphs (full-featured version only)

Add a line to the graph

How to add a line as a second graph?

When you are working with one of the provided packages (polynomials, fraction of polynomials or ellipses), the sub-menu will appeared as on the following picture:

sub-menu to work with added line

When you touch on the "line" circle, the line automatically added to the graph. Tap on one of the green circles to show intersection points, move, rotate or remove it.

The "info" circle is to show the main information of the graph, including x-values of the intersection points (i.e. roots of equation f(x) = ax + b).