Question

The area of rectangular field is 150 sq. units If its perimeter is 50 units then its dimensions are

• A. 27, 5
• B. 3, 50
• C. 5, 30
• D. 10, 15

Answer 1

The correct option is D 10, 15

Let the length and breadth of rectangular field is x and y respt.

Then area =xy=150.................(1)

And perimeter of rectangular field =2x+2y=50

Or x+y=25--------------------------------------(2)

Or x=25-y Put in (1)

So y(25-y)=150

$25y-y^2=150\Rightarrow y^2-25y+150=0\Rightarrow y^2-15y-10y+150=0\Rightarrow y(y-15)-10(y-15)=0\Rightarrow (y-10)(y-15)$

So y=10 or y=15

Or x=25-15=10 or x=25-10=15

Then its dimensions are 10 ,15