Answer:
$25
Step-by-step explanation:
500 mins = $35 (fixed + per minute charge)
1500 mins = $55 (fixed + per minute charge)
If we let per minute charge be "m"
and
let fixed charge be "f"
we can write 2 equations as:
35 = 500m + f
and
55 = 1500m + f
Now,
We re-write both equations in terms of f and equate both expressions:
f = 35 - 500m
and
f = 55 - 1500m
Equating:
35 - 500m = 55 - 1500m
-500m + 1500m = 55 - 35
1000m = 20
m = 20/1000
m = 0.02
Now we find f, what we are looking for:
f = 35 - 500m
f = 35 - 500(0.02)
f = 25
So, the fixed charge is $25
Answer:
150
Step-by-step explanation:
30 + 30 + 45 + 45 = 150
Answer:
39. r = 13.4
40. m = 12
Step-by-step explanation:
39. Given the equation, 
, to solve for r, the following are the correct steps to take to arrive at the solution:
(given)
Add 0.8 to both sides of the equation (addition property of equality)
(this is where the error occurred.)
40. The correct steps to take in solving the equation, 
is as follows:
(given)
Multiply both sides by 3 (multiplication property of equality)
(this is where the error occurred. This is what we should have at this line/step)
(dividing both sides by -1)
Answer: Choice D
==========================================================
Explanation:
Let g(t) be the antiderivative of 
. We don't need to find out what g(t) is exactly.
Recall by the fundamental theorem of calculus, we can say the following:
This theorem ties together the concepts of integrals and derivatives to show that they are basically inverse operations (more or less).
So,
From here, we apply the derivative with respect to x to both sides. Note that the 
portion is a constant, so 
![\displaystyle F(x) = g(x^2) - g(\pi)\\\\ \displaystyle F \ '(x) = \frac{d}{dx}[g(x^2)-g(\pi)]\\\\\displaystyle F\ '(x) = \frac{d}{dx}[g(x^2)] - \frac{d}{dx}[g(\pi)]\\\\ \displaystyle F\ '(x) = \frac{d}{dx}[x^2]*g'(x^2) - g'(\pi) \ \text{ .... chain rule}\\\\](https://tex.z-dn.net/?f=%5Cdisplaystyle%20F%28x%29%20%3D%20g%28x%5E2%29%20-%20g%28%5Cpi%29%5C%5C%5C%5C%20%5Cdisplaystyle%20F%20%5C%20%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bg%28x%5E2%29-g%28%5Cpi%29%5D%5C%5C%5C%5C%5Cdisplaystyle%20F%5C%20%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bg%28x%5E2%29%5D%20-%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bg%28%5Cpi%29%5D%5C%5C%5C%5C%20%5Cdisplaystyle%20F%5C%20%27%28x%29%20%3D%20%5Cfrac%7Bd%7D%7Bdx%7D%5Bx%5E2%5D%2Ag%27%28x%5E2%29%20-%20g%27%28%5Cpi%29%20%5C%20%5Ctext%7B%20....%20chain%20rule%7D%5C%5C%5C%5C)
Answer is choice D
The first one. A is the answer
