Answer:
The length is 10 cm, and the width is 0.5 cm.
Explanation:
First, divide the perimeter by 2 to take off the extra sides.
21 / 2 = 10.5
The total of the sides is 10.5 cm, so now we know:
l + w = 10.5
We know that the length is 9.5 greater than the width, so we can substitute that in for the l.
w + 9.5 + w = 10.5
2w = 1
w = 0.5
The width of the rectangle is 0.5 cm.
10.5 - 0.5 = 10
The length of the rectangle is 10 cm.