Given:
The area model.
To find:
The area as a sum and area as a product.
Solution:
The four terms of the area model are
.
The area as a sum is the sum of all the terms of given area model.
Area as a sum =

=

The area as a product is the factor form of sum of all the terms of given area model.
Area as a product =

=

=

Therefore, the area as a sum is
and the area as a product is
.