A square painting is surrounded by a frame. the outside edges of the frame are x inches in length, and the frame is 3 inches thick. What is the total area of the frame?

A)-12x+36
B)12x-36
C)x^2+12x+36
D)x^2-12x-36

Is it C or D?

4 answers

Here is what I get:

x^2 - (x-3)^2 =

x^2 - (x^2 - 6x + 9) =

x^2 - x^2 + 6x - 9) = 6x - 9

Typos?
the 3" frame is on both sides, so you need

x^2 - (x-6)^2 = 12x-36
A square painting is surrounded by a frame. The outside edges of the frame are x inches in length and there is a 2-inch border between the painting and the frame. What is the total area of the border?
The answer if there is a 2-inch border would be 8x-16
Step by Step:
2(2x) + 2(2)(x - 4)
Multiply 2 times 2x and 2 times 2:
4x + 4 (x - 4)
Use Distributive Property to multiply 4 times x and 4 times - 4 (negative 4):
4x + 4x - 16
Then add like terms, 4x plus 4x:
8x - 16