Given:
The focus of the parabola is at (6,-4).
Directrix at y=-7.
To find:
The equation of the parabola.
Solution:
The general equation of a parabola is:
...(i)
Where, (h,k) is vertex, (h,k+p) is the focus and y=k-p is the directrix.
The focus of the parabola is at (6,-4).
On comparing both sides, we get
...(ii)
Directrix at y=-7. So,
...(iii)
Adding (ii) and (iii), we get
Putting in (ii), we get
Putting 
in (i), we get
Therefore, the equation of the parabola is .
So first of all we need to know that area is length times width
Area = L x W
since we know the area is 42 and the length is 12 lets plug those in
42 = 12 x W
now we dont know what W is yet but we can figure it out by dividing 42 by 12
42/12 = 3.5
So W = 3.5!
but its asking for the perimeter and we know that perimeter is all of the sides of the rectangle added up. Heres a picture
___3.5___
| |
| |
12 | | 12
| |
************
3.5
see now we just add those all up together:)
12 + 12 + 3.5 + 3.5 = 31!!
so our perimeter is 31 inches:)
have a good one
PICK ME BRAINLIEST!:D
Step-by-step explanation:
Given - f(t)=110(1.35)^{\frac{t}{40}}
To find - Write the function in the form f(t)=ae^{kt}. Round all coefficients
to four decimal places.
Proof -
Given that , the function is f(t)=110(1.35)^{\frac{t}{40}}
Now,
We can write it in the form of 
By comparing with the form 
, we get
a = 110.0000
k = 
= 0.0250
3.9+3.9 = 7.8
7.8 * 3.9 * 3 = 91.26
5.7 * 3.9 * 3 = 66.69
66.69 + 91.26 = 157.95
Answer is A
The answer is B. Increasing: No where Decreasing: (0,1) Constant: (-2,∞)
