Question

find the area of rectangle whose length is (1/5x - 1/4y) cm and breadth is (5x × 5x - 4y × 4y) cm.​

Answer 1

Area of revtangle=length*breadth

Length=(1/5x-1/4y)

Breadth =(25x²-16y²)

So multiply both we get 5x³+4y³-16/5xy²-25/4x²y