Question

find the area of a rectangle whose length is thrice its breadth where breadth is 4x

Answer 1

b=4x
l=3x4x
l=12x
Area of rectangle=lxb
=4xx12x
=48x

Answer 2

let at length b l and breadth b b therefore l= 3b , b = 4x, therefore l = 4 x ×3 = 12x area of rectangle=l×b =12x×4x=48x².