fozzzy wrote:

Attachment:

image.jpg

The figure above represents a square plot measuring x feet on a side. The plot consists of a rectangular garden, 48 square feet in area, surrounded by a walkway that is 3 feet wide on two opposite sides and 2 feet wide on the other two sides. What is the value of X?

a) 8

b) 10

C) 12

d) 16

e) 18

Work from the answer choices. I'll pretend I started with E.

If x = 18, the length of the rectangle must be 18 - 2 - 2 (for each part of the walkway) = 14

OR 18 - 3 - 3 = 12 is the length of the rectangle.

Work with 12; it's a factor of 48, the area of the rectangle.

If rectangle length = 12, width is 48/12 = 4.

But that's the side that has 2-foot wide walkways.

Adding both 2-foot walkway parts to the width of the rectangle should yield 18.

4 + 2 + 2 = 8. Not possible. The outside shape is a square. Sides must be equal. 18 and 8 aren't equal.

No need to test rectangle length or width of 14. If 18 were the answer, because the outside is a square, it would yield 18 after taking walkway into account no matter which measure of rectangle side were used.

Try C, x = 12. If so, length of rectangle is 12 - 2 - 2 = 8. (Or 12 - 3 - 3 = 6.)

Work with L=8. If so, rectangle width must be 48/8 = 6.

When calculating rectangle length = 8, we accounted for the two 2-foot wide walkway parts.

So to rectangle width of 6, add the two 3-foot parts of the walkway: 3 + 3 = 6.

6 + 6 = 12, which is the number we need to make the sides be equal.

Answer C (which I chose to test first - got lucky)