9514 1404 393
Answer:
5 hours
Step-by-step explanation:
A quick way to look at this is to compare the difference in hourly charge to the difference in 0-hour charge.
The first day, the charge is $3 more than $12 per hour.
The second day, the charge is $12 less than $15 per hour.
The difference in 0-hour charges is 3 -(-12) = 15. The difference in per-hour charges is 15 -12 = 3. The ratio of these is ...
$15/($3/h) = 5 h
The charges are the same after 5 hours.
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If you write equations for the charges, they will look like ...
y1 = 15 + 12(x -1)
y2 = 3 + 15(x -1)
Equating these charges, we have ...
15 +12(x -1) = 3 + 15(x -1)
12x +3 = 15x -12 . . . . . . . . eliminate parentheses
15 = 3x . . . . . . . . . . add 12-12x
x = 15/3 = 5 . . . . . . divide by 3
You might notice that the math here is very similar to that described in words, above.
The charges are the same after 5 hours.
The new perimeter would be 60. because the width and the height are doubled.
So D would be going up because it is positive. It is going up 10ft, once again cause the integer is a positive 10. Now E will be going down because it is a negative. Therefore it will go down 15ft for the reason being the integer is negative 15. Hope this helps.
Answer:
see below
Step-by-step explanation:
We can determine how much 12 ounces cost by using ratios
5 ounces 12 ounces
-------------- = -------------------
2.35 x
Using cross products
5x = 12*2.35
5x = 28.2
Divide each side by 5
5x/5 = 28.2/5
x =5.64
If she has 10 dollars
5 ounces y ounces
-------------- = -------------------
2.35 10
5*10 = 2.35y
50 = 2.35y
Divide each side by 2.35
50/2.35 = 2.35y/2.35
21.27659574 =y
She can buy 21.3 ounces
The answer is C (289pi/6 mi2)