Q2 of 8 Page 56

The length of a rectangle is 1 metre more than its breadth. Its area is square metres. What are its length and breadth?

Let the length be ‘x’ and breadth be ‘y’.


Length = Breadth + 1


⇒ x = y + 1 … (1)


Area of rectangle = Length × breadth



⇒


⇒


⇒


⇒ 15 = 4(y2 + y)


⇒ 15 = 4y2 + 4y


⇒ 4y2 + 4y – 15 = 0


⇒ 4y2 – 6y + 10y – 15 = 0


⇒ 2y (2y – 3) + 5(2y – 3) = 0


⇒ (2y – 3) (2y + 5) = 0


2y – 3 = 0 or 2y + 5 = 0




Hence, side of a rectangle cannot be negative. Therefore,


Put in equation (1)


⇒


⇒


⇒


∴ The length is metre and breadth are metre.


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