Question

Identities in algebra can sometimes be shown as area relationships. Draw figures corresponding to the identities (a + b)(a − b) = a² − b² and (a + b + c)² = a² + b² + c² + 2ab + 2bc + 2ca.

A square of side b is removed from a corner of a square of side a, as shown. The area of the shaded region can be written as