Question

Find the area of the rectangle whose length and breadth are 5a+4b and 4a-5b respectively​

Answer 1

Step-by-step explanation:

Area of rectangle = length×breadth

=> (5a+4b)×(4a-5b)

=> 5a(4a-5b) +4b(4a-5b)

=> 20a^2 - 25ab + 16ab - 20b^2

=> 20a^2 - 9ab - 20 b^2 ( Ans)