Answer:
x = 3.75 inches
Step-by-step explanation:
We have,
Perimeter of a rectangle, P = 21 inches
Its length is 3 inches greater than its width. Let width is x. So, length of rectangle is l = 3+x
The perimeter of a rectangle is :
[tex]P=2(l+b)[/tex]
l is length and b is breadth
Here, l = 3+x, b = x
Perimeter :
[tex]P=2(3+x+x)\\\\21=2(3+2x)[/tex]
[tex]21=6+4x\\\\15=4x\\\\x=3.75\ \text{inches}[/tex]
So, the width is 3.75 inches.
