How to Find Intersection Between Graphs in GeoGebra

You can either use CAS, or Algebra View and Graphics View together, to find the points of intersection between graphs. Instructions for both methods are detailed below.

GeoGebra Instruction 1

Using CAS

1.
Open CAS under GeoGebra icon View in GeoGebra icon Menu.
2.
Type f(x) in CAS as

f(x) :=

and press Enter. Do the same with g(x).

3.
In an empty row in CAS, type

f = g

and click Solve GeoGebra icon in Toolbar. You should get a list of solutions.

4.
For each of the solutions x in the list from Step 3, type

(x,f(x))

in an empty row in CAS and press Enter. GeoGebra then displays the points of intersection.

Screenshot of GeoGebra showing the intersection of a parabola and a line

GeoGebra Instruction 2

Using Algebra View and Graphics View

1.
Open Algebra View and Graphics View under GeoGebra icon View in GeoGebra icon Menu.
2.
Type f(x) into Algebra View and press Enter. Do the same with g(x). These now appear as functions in Algebra View and as graphs in Graphics View.
3.
In Toolbar, click Intersect GeoGebra icon (it is under the same menu as the Point GeoGebra icon tool).
4.
Click both graphs. The order does not matter.
5.
You will now find the points of intersection displayed in Algebra View.

Screenshot of GeoGebra showing the intersection of a parabola and a line

If you wish, you can additionally choose the axes to find the intersection between a graph and the axes.

Want to know more?Sign UpIt's free!