Answer:
20 ft by 60 ft
Step-by-step explanation:
"What should the dimensions of the garden be to maximize this area?"
If y is the length of the garden, parallel to the stream, and x is the width of the garden, then the amount of fencing is:
120 = 3x + y
And the area is:
A = xy
Use substitution:
A = x (120 − 3x)
A = -3x² + 120x
This is a downward facing parabola. The maximum is at the vertex, which we can find using x = -b/(2a).
x = -120 / (2 · -3)
x = 20
When x = 20, y = 60. So the garden should be 20 ft by 60 ft.
Area of Rectangle = length times width
lets say length = 2x-4
width = x+5
Note: you can switch these around, width could be 2x-4 and length could be x+5, it doesnt matter.
With that being said:
length * width = area
(2x-4)(x+5)=area
FOIL (First Outer Inner Last)

Simplify:
Answer:
g(-5) = -5
Step-by-step explanation:
You replace x with -5.
-3(-5) + 10 = -15
-15 + 10 = -5
The answer is -5.
Answer:
Sorry if I get it wrong:
Answer: 3,840in
Step-by-step explanation: