We can define a rectangle as a four sided quadilateral whose all internal angles are right angles.

Since a rectangle is a 2 – dimensional shape, so its surface area is the same as its area.

**Formula to calculate the surface area of a rectangle.**

**Example:**

Calculate the surface area of a rectangle whose length is 10 cm and width 5 cm.

Therefore, the surface area of the rectangle is 50 cmÂ².