Question

perimeter and area of rectangle are 28 metres and 40 m square then find length and breadth

Answer 1

Perimeter =2 (l +b) = 28 m

= l+b = 14.

= l = 14- b. - (1)

Area = lb =40m^2 - (2)

Substitute (1) in (2)

lb=40

(-b+14)b = 40

-b^2 + 14b = 40

0 =b^2 - 14b +40

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

b(b-4) - 10(b-4) =0

(b-4)(b-10)=0

b= 4,10

When b=4m

lb = 40m

4l = 40

l =40/4 =10 m

When b =10

lb =40m

10l =40

l=40/10 =4 m

Therefore, length is 4m or 10 m and breath is 4m or 10m