Question

For a rectangle area 40sq.cm and perimeter 28cm.find the length and breath of the rectangle?

Answer 1

Let the length of rectangle be x and breadth be b.

Area of triangle = l*b

40 = l*b

b=40/l cm

Perimeter of triangle = 2(l+b)

28 = 2(l+40/l)

14=(l^2+40)/l

14l=l^2+40

l^2-14l+40=0

l^2-10l-4l+40=0

l(l-10)-4(l-10)=0

(l-4)(l-10)=0

l=4cm or l=10cm

b=40/l = 10cm or 4cm