Answer: 
Step-by-step explanation:
The perimeter of a rectangle can be calcualated with this formula:

Where "l" is the lenght and "h" is the height.
The area of a rectangle can be found with this formula:

Where "l" is the lenght and "h" is the height.
In this case we know that:

Therfore, we can susbsitute them into
and solve for "h" in order to find its value:

Find two number whose sum is 3 and whose product is -40. These are -5 and 8. Then, factorizing, we get:

The positive value is the height. Then:

Since the length is 3 centimeters greater than its height, we get that this is: Then:

Substituting values into
, we get that the perimeter is:

5x+3y+6x+9y
All you'd need to do is combine like terms. So add 5x to 6x and add 3y to 9y.
(5x+6x)+(3y+9y)
Final Answer: 11x + 12y
The mathematical expression is
5x = 1/4
Divide:
x = (1/4)/5 = (1/4)*5 = 5/4 (ANSWER)
Answer:
Surface area = 4 π r2 square units
Step-by-step explanation: