Hello mastermin346(a) Let's suppose there are rows.

In row there are blocks.

In row there are blocks.

In row there are blocks.

...

In row there are blocks.

So if there are blocks in the top row:So there are rows.

(b) The area of each block

So we need to find the number of blocks altogether and multiply by .

That total number, , is:If we write the sum backwards:

and add the two together:

So the area .

Grandad