<em><u>The system of equations that represents this situation are:</u></em>
q + p = 2
4q + 5p = 8
<em><u>Solution:</u></em>
Let q be the number of hours it took Courtney to walk from her house to the beach
Let p be the number of hours it took her to walk from the beach to the park
<em><u>The entire walk took 2 hours</u></em>
Therefore,
q + p = 2 ------- eqn 1
<em><u>The total distance Courtney walked was 8 kilometers</u></em>
Total distance = 8 km
Courtney walked from her house to the beach at a constant speed of 4 kilometers per hour
Then walked from the beach to the park at a constant speed of 5 kilometers per hour
<em><u>Distance is given as:</u></em>

<em><u>From her house to the beach:</u></em>

<em><u>From the beach to the park:</u></em>

We know that,
Total distance = 8 km
Therefore,
4q + 5p = 8 ------ eqn 2
<em><u>Thus the system of equations that represents this situation are:</u></em>
q + p = 2
4q + 5p = 8
Answer: A. divided the difference of the two quantities by the sum of the two quantities.
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Explanation:
The difference of the quantities is 20-15 = 5
The sum of the quantities is 20+15 = 35
Dividing those results leads to 5/35 = 0.142857 which rounds to 0.1429
That converts to 14.29%
This is likely the path Adam took. This path is incorrect. The correct steps are shown below
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Difference = 20-15 = 5
Divide the difference over the original quantity
5/20 = 1/4 = 0.25 = 25%
We have a 25% decrease because the new quantity (15) is smaller than the old quantity (20)
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Here's another way to approach the problem
A = old value = 20
B = new value = 15
C = percent change
C = [ (B-A)/A ] * 100%
C = [ (15-20)/20 ] * 100%
C = (-5/20)*100%
C = -0.25*100%
C = -25%
The negative C value means we have a negative percent change, ie we have a percent decrease. So this is another way to get a 25% decrease.
From the table we can see:
Number of songs: Cost:
0 $ 0
1 $1.25
2 $2.50
3 $3.75
4 $5.00
Therefore the rate of change is: (2.50 - 1.25) / ( 2 - 1 ) = $1.25
Answer:
It means that : C. The cost increases $1.25 for each additional song that is downloaded.
(4,1) because it is the ordered pair that passes through the line