SOLUTION: The area of a square in square feet is represented by 4z^2-36z+81. Find an expression for the perimeter of the square. Then find the perimeter when z=10 feet. Expression: ______

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: The area of a square in square feet is represented by 4z^2-36z+81. Find an expression for the perimeter of the square. Then find the perimeter when z=10 feet. Expression: ______      Log On


   

Question 850419: The area of a square in square feet is represented by 4z^2-36z+81. Find an expression for the perimeter of the square. Then find the perimeter when z=10 feet.
Expression: ________________
Perimeter when z=10 feet: ____________________
Found 2 solutions by Seutip, harpazo:
Answer by Seutip(231) About Me  (Show Source):
You can put this solution on YOUR website!
Since this is the area 4z%5E2-36z%2B81 and finding for the area of square is
A+=+s%5E2 where s is the side, the perimeter P=4s.
In the area 4z%5E2-36z%2B81, we can factor it to
4z%5E2-36z%2B81+=+%282z-9%29%282z-9%29
Therefore 4z%5E2-36z%2B81+=+%282z-9%29%5E2 ans s = 2z-9
And the perimeter
P= 4(2z-9)
If z=10, substitute
P = 4(2(10)-9)
P = 4(20-9)
P = 4(11)
P = 44 feet :)
Hope that helps.
#rda33

Answer by harpazo(655) About Me  (Show Source):
You can put this solution on YOUR website!
Area of square = (side)^2

Perimeter of square = 4(side).

The area given is 4z^2-36z+81.

Use A = (side)^2 to find the side.
sqrt(4z^2-36z+81) = sqrt{(side)^2}

You take it from here. Ok?