Answer:
A) Dimensions;
Length = 20 m and width = 10 m
B) A_max = 200 m²
Step-by-step explanation:
Let x and y represent width and length respectively.
He has 40 metres to use and he wants to enclose 3 sides.
Thus;
2x + y = 40 - - - - (eq 1)
Area of a rectangle = length x width
Thus;
A = xy - - - (eq 2)
From equation 1;
Y = 40 - 2x
Plugging this for y in eq 2;
A = x(40 - 2x)
A = 40x - 2x²
The parabola opens downwards and so the x-value of the maximum point is;
x = -b/2a
Thus;
x = -40/2(-2)
x = 10 m
Put 10 for x in eq 1 to get;
2(10) + y = 40
20 + y = 40
y = 40 - 20
y = 20m
Thus, maximum area is;
A_max = 10 × 20
A_max = 200 m²
Answer:
y = -3x + 2
Step-by-step explanation:
y = mx + b
m = rise/run = -6/2 = -3
(negative graph = negative slope)
b = y-intercept = 2
You multiply 3.25 x 5280 to get 17102.2 feet.
