Given:
The power generated by an electrical circuit (in watts) as a function of its current x (in amperes) is modeled by

To find:
The current which will produce the maximum power.
Solution:
We have,


Differentiate with respect to x.

...(i)
To find the extreme point equate P'(x)=0.


Divide both sides by -30.

Differentiate (i) with respect to x.

(Maximum)
It means, the given function is maximum at x=4.
Therefore, the current of 4 amperes will produce the maximum power.
Since the price is now 15% less you would first find what 15% of 25 is by using 25*.15 and get 3.25 then you subtract that from 25 and get 25-3.25= $21.75
Answer: The length is 13 inches and the width is 11 inches.
Step-by-step explanation:
Let L represent the length of the rectangle.
Let W represent the width of the rectangle.
The formula for determining the area of a rectangle is expressed as
Area = LW
The area of the rectangle is 143 square inches. This means that
LW = 143 - - - - - - - - - - - - --1
The rectangle's length is 2 in more than its width. This means that
L = W + 2
Substituting L = W + 2 into equation 1, it becomes
W(W + 2) = 143
W² + 2W - 143 = 0
W² + 13W - 11W - 143 = 0
W(W + 13) - 11(W + 13) = 0
W + 13 = 0 or W - 11 = 0
W = - 13 or W = 11
Since the width cannot be negative, it means that W = 11
L = W + 2 = 11 + 2
L = 13
Answer:
r = 7
Step-by-step explanation:
To solve this, we can plug in a pair of x and y values and solve for r.
y = rx | Plug in a pair
42 = r*6 | Now divide both sides by 6
7 = r.
We can test this by plugging in r with a pair.
y = (7)x
77 = 7*11, 77 = 77, This equation is correct.
Answer:
a= k/4+9b
Step-by-step explanation:
hope this helps, if not let me know!