Ziggurat formula

This task is about using equations to work out attributes of a ziggurat shape.


 

This shape is called a ziggurat and is three blocks high (n = 3). Each block is 1 metre high.
 
Here is a rule for the number of blocks in a ziggurat that is n blocks high:
 
bn n is the height of the ziggurat.
bn is the number of blocks in a ziggurat that is n blocks high.
 
a) How many blocks are there in a ziggurat that is
 
 
i)
 
ii)
3 blocks high? __________
 
12 blocks high? __________
 
Each face on a block in the ziggurat has an area of 1 m2. This formula gives the total surface area for ziggurats of different heights:
 
an = 8n2 - 4n + 1

n is the height of the ziggurat.
an is the total surface area (in m2) of a ziggurat that is n blocks high.
 

b) What is the total surface area of a ziggurat that is
 
 
i)
 
ii)
3 metres high? __________ m2
 
10 metres high? __________ m2