Answer:
Step-by-step explanation:
Let the time flown by the flying carpet be 
. Then, we have that 
.
We multiply both sides of the equation by to get 
.
We subtract 
from both sides to get 
.
We divide both sides of the equation by 
.
We know that the speed of the flying carpet in still wind is the average of the rates of the speed of the flying carpet with the wind and against the wind.
The speed with wind is 
mph.
The speed against wind is 
mph.
The speed in still wind is 
.
Therefore, the answer is 
and we're done!
Answer:
Step-by-step explanation:
Let the other side of the rectangle be y. The perimeter of the rectangle is expressed as P = 2(x+y)
Given P = 30ft, on substituting P = 30 into the expression;
30 = 2(x+y)
x+y = 15
y = 15-x
Also since the area of the rectangle is xy;
A = xy
Substitute y = 15-x into the area;
A = x(15-x)
A = 15x-x²
The function that models its area A in terms of the length x of one of its sides is A = 15x-x²
The side of length x yields the greatest area when dA/dx = 0
dA/dx = 15-2x
15-2x = 0
-2x = -15
x = -15/-2
x = 7.5 ft
Hence the side length, x that yields the greatest area is 7.5ft.
Since y = 15-x
y = 15-7.5
y = 7.5
Area of the rectangle = 7.5*7.5
Area of the rectangle = 56.25ft²
Answer:
b^2-c^2-10b+10c
Step-by-step explanation:
b^2-c^2-10(b-c)
b^2-c^2-10b+10c
Step-by-step explanation:
X +1 + X + 2
X + X + 1 + 2
2x + 3
Therefore it's 2x + 3
