Question

a room length is 15m and width 12m around a 90square m verandah then find the verandah width?

Answer 1

Let the width of verandah  =w

Area of the room = 15*12 = 180m²

Length and width of the room including verandah will be 15+2w and 12+2w

Area of the room including verandah = (15+2w)(12+2w)

Area of verandah = Area of room including verandah - Area of room 
                             90 = (15+2w)(12+2w) - 180
270 = (15+2w)(12+2w)
4w²+54w-90 = 0

Solving it, w = 3/2 = 1.5 

Width of verandah = 1.5 m