How to Draw a Triangle in Python Turtle

Python has a simple pen drawing library called turtle. Using simple movement commands, we can draw shapes using the python turtle library. When teaching python to children, turtle is a good library to introduce to get children excited about the language and its features.

The basic actions used in the following examples are,

  • Draw a line with pen - forward() command
  • Move without drawing - penup(), pendown() commands
  • Turn the pen to an angle - left(), right() commands

The following python program draws a simple equilateral triangle,

import turtle

board = turtle.Turtle()

board.forward(100) # draw base

board.left(120)
board.forward(100)

board.left(120)
board.forward(100)

turtle.done()

The following python program draws a right angled triangle,

import turtle

board = turtle.Turtle()

board.forward(100) # draw base

board.left(90)
board.forward(100)

board.left(135)
board.forward(142)

turtle.done()

The following python program draws a star shape by drawing two identical isosceles triangles,

import turtle

board = turtle.Turtle()

# first triangle for star
board.forward(100) # draw base

board.left(120)
board.forward(100)

board.left(120)
board.forward(100)

board.penup()
board.right(150)
board.forward(50)

# second triangle for star
board.pendown()
board.right(90)
board.forward(100)

board.right(120)
board.forward(100)

board.right(120)
board.forward(100)

turtle.done()