SOLUTION: At a tennis club, a 18,000ft2 rectangular area is partitioned into three rectangular courts of equal size. A total of 920feet of fencing is used to enclose the three courts, includ

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Question 955843: At a tennis club, a 18,000ft2 rectangular area is partitioned into three rectangular courts of equal size. A total of 920feet of fencing is used to enclose the three courts, including the interior sides. What are the possible dimensions, in feet, of the entire rectangular area?
Select all that apply.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
Draw a rectangle with with two segments vertically, forming the three equal partitions of the region. Call the horizontal distance or dimension, x; and call the vertical dimension, y.

AREA: xy=18000
FENCE MATERIAL: 2x+2y+y+y=920

system%28xy=18000%2C2x%2B4y=920%29

Skipping over a few steps,....
%28460-2y%29y=18000
%28230-y%29y=9000
.
y%5E2-230y%2B9000=0
-
The discriminant of the quadratic equation is.... %28130%29%5E2. You would continue with the general solution formula and say highlight%28y=%28230%2B-+130%29%2F2%29.

Trying the MINUS form just to take a value,
highlight%28y=50%29;
The other dimension, x=460-2y,
highlight%28x=360%29.

Using the PLUS form,
finding that highlight%28y=180%29__________highlight%28x=100%29.

Both combinations will work.