Question

if the side of a rectangle are in the ratio 9:5 and it's perimeter is 42 cm , find its area​

Answer 1

Answer:

101.25cm^2

Step-by-step explanation:

Let the common factor be x.

Thus the sides of the rectangle are 9x and 5x.

Perimeter of rectangle- 2(l+b)

P=2(9x+5x)

We know the perimeter is 42cm.

42=2(14x)

42=28x

x=1.5

Thus the sides are

(9×1.5) And (5×1.5)

13.5 and 7.5

Area= 13.5×7.5 (length×breadth)

Area=101.25cm^2

Answer 2

Step-by-step explanation:

Let length =9x

breadth=5x

Perimeter of rectangle=2 (l+b)

42 cm =2 (9x+5x)

42÷2 = 14x

21 =14x

21÷14 =x

1.5cm =x

Length = 9×1.5=13.5cm

Breadth =5×1.5=7.5cm

Area of rectangle =length×breadth

=(13.5×7.5)cm

=101.25cm square