Answer: Raymond is correct
The DJ charges $75 an hour.
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Explanation:
x = number of hours
y = total cost
The DJ does a 3-hour event for $275. This means one point is (x,y) = (3,275)
Another point is (5,425) because a 5-hour event costs $425.
Let's find the slope of the line through these two points.
The slope is 75, meaning that each time y goes up by 75, x goes up by 1.
Flipped around it means each time x goes up by 1, y goes up by 75.
This means each time we add on an extra hour, the cost goes up by $75.
The DJ charges $75 an hour. Raymond is correct.