Triangles in the Coordinate Plane

show perimeter
show area

This Demonstration allows you to manipulate the endpoints of a triangle in a Cartesian coordinate system and finds the perimeter and area of the triangle. The perimeter is found by summing the distances between the endpoints of successive sides and the area is found using Heron's formula.

Details

Heron's formula: If

a

,

b

, and

c

are the side lengths of the triangle, define

s=

1

2

(a+b+c)

, the semiperimeter of the triangle. Then the area is given by

s(s-a)(s-b)(s-c)

.

External Links

Heron's Formula (Wolfram MathWorld)

Permanent Citation

Ed Zaborowski, Kris Climer

"Triangles in the Coordinate Plane"
http://demonstrations.wolfram.com/TrianglesInTheCoordinatePlane/
Wolfram Demonstrations Project
Published: September 28, 2007