Question

Mark the correct alternative in the following question:

The length and breadth of a rectangle of area A are doubled. The area of the new rectangle is

(a) 2A (b) A² (c) 4A (d) None of these

Answer 1

Let the length and breadth of the given rectangle be l and b, respectively.

We have,
A = lb .....(i)

Also,
the length of the new rectangle, l' = 2l and
the breadth of the new rectangle, b' = 2b

Now, the area of the new rectangle = l' $\times$ b'
= (2l) $\times$ (2b)
= 4lb
= 4A [Using (i)]

Hence, the correct alternative is option (c).