Answer:
Length: 21 cm and Width: 6cm
Step-by-step explanation:
Let
be the width and
length of the rectangle. We know:
-------- eq. 1
(Perimeter of the rectangle) ------- eq. 2
Substitute equation 1 in equation 2:

Using the value of y, we find x.

I think the answer would have to be C if I am right
Answer included, round as you need
HERE IS YOUR ANSWER IN PICTURE...
Do you mean 3 to the third power or three times three? Three to the third power would be three times three times three which is 27. But just three times three is 9