Question

the perimeter of a rectangular garden , whose length is 4m more than its width is 40m. find the dimensions of the rectangle

Answer 1

let the width of rectangle(b) = x m.
  then length(l) = (x+4) m.
a/q,
       perimeter of rectangle = 40 m.
or,   2(l+b) = 40 
or,    2(x+4+x) = 40
or,  2(2x+4) =40
or,  4x+8 =40
or,   4x = 40-8
or,   x = 32/4
       x= 8
so, width(b) = x = 8 m.
And, length(l) = x +4  = 12 m
therefore its dimension is 12m×8m

Answer 2

let the width of the rectangle be x
given that the length is 4m more than its width
so the length of the rectangle be x+4
And perimeter=40m
perimeter of a rectangle is
p=2(l+b)
Replacing p=40,l=x+4 and b=x
we get
40=2(x+4+x)
40=2(2x+4)

dividing both sides by 2
20=2x+4
adding -4 on both sides
2x+4-4=20-4
2x=16
dividing both isdes by 2
2x/2=16/2
x=8
Thus the width of the rectangle be 8m
and the length of the rectangle be
x+4=8+4=12m
length of the rectangle be 12m