Question

half the perimeter of a rectangle whose length is 6 centimetre more than its breadth is 30 find its area

Answer 1

perimeter of the rectangle=2(l+b)

half of the perimeter=30

let breadth=X

then length is 6cm more than its breadth

so length=X+6

2(l+b)/2=30

2((x+6)+(x))/2=30

2(2X+6)=30×2

2(2X+6)=60

2X+6=60/2

2X=30-6

2X=24

X=24/2

X=12

then length= 12cm which is X+6

then X= 12-6=6cm which is the breadth

then area of a rectangle is =length×breadth

=12×6

=72cm^2