wiz-icon
MyQuestionIcon
MyQuestionIcon
4
You visited us 4 times! Enjoying our articles? Unlock Full Access!
Question

The perimeter of a rectangle is 20cm and the difference between its length and breadth is 4cm.
Find the length and breadth of the rectangle.

Open in App
Solution

Let the length and breadth of the rectangle be x cm and y cm repectively
So, as per the first condition
2(x+y)=20 -------------(1)
Again,
as per the second condition
xy=4-------------(2)
Now,
solving equation (1),(2) by using determinant method
2(x+y)=20 -------------(1)

x+y=10
xy=4-------------(2)

D=1111=1×1(1)×1
=1+1
=2

Dx=41101=4×1(1)×10
=4+10
=14

Now,
Dy=14110=1×101×4
=104
=6
Again,

x=(Dx)D and y=(Dy)D

So, x=(14)2=7 and y=(6)2=3

Hence the length and breadth of the rectangle are 7cm and 3cm respectively.

flag
Suggest Corrections
thumbs-up
1
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Cramer's Rule
MATHEMATICS
Watch in App
Join BYJU'S Learning Program
CrossIcon