Question

the length of a rectangle is greater than the breadth by 3. if the length is increased by 9 cm. and the breadth is reduced by 5 cm , the area remains the same , find the dimensions of the reactangle​

Answer 1

Answer:

l=18cm     b=15cm

Step-by-step explanation:

l=b+3

(l+9)*(b-5)=lb

lb+9b-5l-45=lb

9b-5l=45

9b-5(b+3)=45

9b-5b-15=45

4b=60

b=15cm

l=18cm

Answer 2

Answer:

Step-by-step explanation:

Let the breadth be x cm .

Length = x + 3 cm.

Area of first rectangle = x * (x +3) ---- (1)

Now,  

Given that length is increased by 9 cm = x + 3 + 9 = x + 12 cm.

Given that breadth is reduced by 5cm = x - 5 cm.

Area of the rectangle = (x+12)(x-5).   -------------- (2)

Also given area of rectangle remains same.

x(x+3) = (x + 12)(x-5)

x² + 3x = x²+7x - 60

4x = 60

x = 15.

Thus Breadth = 15 cm.

        Length = 15 + 3  = 18 cm.