The Heron’s formula is a famous formula used to calculate the area of a triangle based on the length of its three sides. It is called “Heron’s Formula” (sometimes called Hero’s formula) after Hero of Alexandria who was a Greek Engineer and Mathematician in 10 – 70 AD.

#### Python Task

Your task is to write a function called

*calculateTriangleArea()*. Your function will:

- Take three parameters corresponding to the length of the 3 sides of a triangle:
*a*,*b*and*c*, - Apply Heron’s formula to calculate the area of the triangle,
- Return the area of the triangle.

You will also then need to create a small program that will:

- Ask the user to enter the length of the three sides of a triangle,
- Calculate the area of the triangle using the
*calculateTriangleArea()*function, - Output the area of the triangle.

#### Video Tutorial

#### Python Code

#### Test Plan:

Once your code is done, complete the following tests to check it is working as expected:

Test # | Input Values (in cm) | Expected Output (in cm^{2}) |
Pass/Fail? |

#1 | First side: 3 Second side: 4 Third side: 5 |
Area: 6 | |

#2 | First side: 8 Second side: 10 Third side: 12 |
Area: 39.686 | |

#3 | First side: 4 Second side: 8 Third side: 10 |
Area: 15.199 |

#### Extension Task #1

Create some extra functions to calculate the area of a square, of a rectangle and of a disc. Each function will need to accept the relevant parameters needed to calculate the area of the desired shape.

#### Extension Task #2

Create a menu system, where the user is asked what shapes they would like to calculate the area of before being asked to enter the relevant dimensions.

#### Did you know?

Hero published a well-recognized description of a steam-powered device called an aeolipile (sometimes called a “Hero engine”). Among his most famous inventions was a windwheel, constituting the earliest instance of wind harnessing on land.