9514 1404 393
Answer:
2πr cm
Step-by-step explanation:
The circumference of a circle of radius r is ...
C = 2πr
For a radius of (r cm), the circumference is ...
A = 2π(r cm) = 2πr cm
For a radius of (2r cm), the circumference is ...
B = 2π(2r cm) = 4πr cm
Then the difference between the circumferences is ...
B -A = (4πr cm) -(2πr cm) = 2πr cm . . . . difference in circumference
Answer:
0, -2, 2, -1
Step-by-step explanation:
You are trying to make it so that the one of the ( )= 0.
An example is (x+15) or (2x+3)
the first l one would be x= -15 since -15+15 would equal 0.
The second one is -3/2 since it would be -3+3 which would equal 0.
also since the equation starts with x( or -x it doesn't really matter) one of the zeros would also be 0.
Hope this helps!
Answer:
1. 169π ft²
2. 144π in²
3) 25π yd²
Step-by-step explanation:
1) π * 13²
π * 169
units = ft²
169π ft²
2) π * 12²
π * 144
units = in²
144π in²
3)π * 5²
π * 25
units = yd²
25π yd²
If my answer is incorrect, pls correct me!
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-Chetan K
Answer:
- 12 ft parallel to the river
- 6 ft perpendicular to the river
Step-by-step explanation:
The least fence is used when half the total fence is parallel to the river. That is, the shape of the rectangle is twice as long as it is wide.
72 = W(2W)
36 = W²
6 = W . . . . . . the width perpendicular to the river
12 = 2W . . . . the length parallel to the river
_____
<em>Development of this relation</em>
Let T represent the total length of the fence for some area A. Then if x is the length along the river, the width is y=(T-x)/2, and the area is ...
A = xy = x(T -x)/2
Note that the equation for area is that of a parabola with zeros at x=0 and at x=T. That is, for some fence length T, the area will be a maximum at the vertex of this parabola. That vertex is located halfway between the zeros, at ...
x = (0 +T)/2 = T/2
The corresponding area width (y) is ...
y = (T -T/2)/2 = T/4
Equivalently, the fence length T will be a minimum for some area A when x=T/2 and y=T/4. This is the result we used above.
