Area of rectangle is product of its length and breadth.
If length is 10units and breadth is 20 units then area will be 10*20= 200 sq. Units
All formuale given for reference below.
https://www.mathsisfun.com/area.html&ved=2ahUKEwjD46Ca56vdAhWLrY8KHaInB6oQFjAJegQIARAB&usg=AOvVaw0fsaEwc8tFFNKLEqQGp0hX
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