SOLUTION: Could someone help me with these 2 problems? 1. Acme Electric Company’s monthly bill includes a basic customer charge of $12.00, and a usage charge of $0.07 for each kilowatt ho

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Question 144965: Could someone help me with these 2 problems?
1. Acme Electric Company’s monthly bill includes a basic customer charge of $12.00, and a usage charge of $0.07 for each kilowatt hour of electricity supplied.
(a) Write an equation that can be used to determine the monthly bill, given the number of kilowatt hours h supplied.


(b) Determine the electric bill if 1850 kilowatt hours of electricity are supplied.



2. Consider the points (4, –1) and (7, 8).
(a) Find the midpoint of the line segment with the given endpoints.



(b) Find the distance between the points. Give an exact answer (simplified as much as possible), and also an approximation to three decimal places.

Answer by solver91311(24713) About Me  (Show Source):
You can put this solution on YOUR website!
1. a. Since every kilowatt-hour costs $0.07, you simply multiply the number of kw-hrs used by 0.07. If you used h kw-hrs, then the variable cost would be 0.07h. Then you need to add the basic charge -- the amount you would have to pay even if you used no electricity at all that month, namely $12.00. So the formula becomes:

C%5Bt%5D=0.07h%2B12.00 where C%5Bt%5D is the total cost for the month.

1. b. Simply substitute 1850 for h and do the arithmetic.

2. a. Use the midpoint formulas. Decide which of your points will be number 1 and which number 2 (It doesn't matter which) and then substitute the coordinate values into:

x%5Bm%5D=%28x%5B1%5D%2Bx%5B2%5D%29%2F2 and y%5Bm%5D=%28y%5B1%5D%2By%5B2%5D%29%2F2 to derive the coordinates of the mid-point, (x%5Bm%5D,y%5Bm%5D)

2. b. Use the distance formula. Again, decide which point will be 1 and which will be 2.

D=sqrt%28%28x%5B1%5D-x%5B2%5D%29%5E2%2B%28y%5B1%5D-y%5B2%5D%29%5E2%29.

Leave your answer in terms of the radical if the number is not a perfect square to get the exact answer. You may want to see if you can simplify the radical by factoring out perfect squares from the radicand. For example, sqrt%288%29=sqrt%284%2A2%29=sqrt%284%29%2Asqrt%282%29=2sqrt%282%29

Use your calculator to get a numerical approximation of the square root and then round to three places as instructed.