You are not logged in.
login | register
Activity: Triangle area, formula (Coordinate Geometry) - Math Open Reference
Tool Thumbnail

Go to: (opens a new window)

An interactive applet and associated web page that calculate the area of a triangle using the formula method in coordinate geometry. The applet has a triangle with draggable vertices. As you drag them the triangle's area is recalculated from the vertex coordinates using the formula.

The grid and coordinates can be turned on and off. The area calculation can be turned off to permit class exercises and then turned back on the verify the answers. The applet can be printed as it appears on the screen to make handouts.

The web page has a full description of the method for determining area using the formula method, a worked example and has links to other pages relating to coordinate geometry.

Applet can be enlarged to full screen size for use with a classroom projector. After use in the classroom, student can access it again from any web browser at home or in the library with no login required.

This resource is a component of the Math Open Reference Interactive Geometry textbook project at

Technology Type: Flash 
Author: John Page
Language: English 
Cost: Does not require payment for use

Average Rating:  [0] Login to rate this resource
My MathTools: Login to Subscribe / Save This
Reviews: be the first to review this resource
Discussions: start a discussion of this resource

Courses: Geometry Coordinate geometry, Triangles, Perimeter, area, and volume