Question

The length of a rectangle is 5 centimeters less than its width. What’s re the dimensions of the rectangle if it’s area is 300 square centimeters?

I need the length of one of the side and the width

Answer 1

Answer: The length of rectangle is 15 cm and width is 20 cm

Explanation:

As according to question

Let the width of rectangle = x cm

Length of rectangle =(x- 5) cm

Area of rectangle is 300 cm²

As we know Area of rectangle is given by

`Area = length * breadth \\\\\Rightarrow 300 = (x-5)x\\\\\Rightarrow 300 = x^2-5x\\\\\Rightarrow x^2-5x-300 = 0 \\\\\Rightarrow x^2-20x+15x-300 = 0 \\\\\Rightarrow x(x-20) +15(x-20) =0\\\\\Rightarrow (x-20)(x+15)=0`

Therefore either (x-20)= 0 or (x+15)=0

i.e. either x= 20 or x = -15

Now width can not be negative

Therefore it cant be -15

Hence the width is 20 cm

Length = x- 5 = 20-5 = 15 cm

Hence the length of rectangle is 15 cm and width is 20 cm