9514 1404 393
Answer:
Explanation:
You are given two ordered pairs:
(years after 1990, cost per credit hour) = (x, C) = (0, 99) and (7, 176)
(Note that 1997 is 7 years after 1990.)
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The "slope" or "rate of change" of the linear model of this relationship is found from ...
m = (change in C)/(change in x) = (176 -99)/(7 -0) = 77/7 = 11
Then the linear model will be ...
C = mx + b . . . . . for some value of b
Using the first ordered pair (x, C) = (0, 99), we can find b:
99 = 11×0 +b
99 = b
So, the linear equation for cost of a credit hour can be written ...
C = 11x +99
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The year 2000 is 10 years after 1990, so the cost when x=10 is ...
C = 11×10 +99 = 209
In the year 2000, tuition will be $209 per credit hour.
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To answer the last question, we need to find x when C = 231. Put this in the equation, and solve:
231 = 11x +99
132 = 11x . . . . . . . subtract 99
132/11 = x = 12 . . . divide by 11
12 years after 1990 is 2002.
In the year 2002, tuition will be $231 per credit hour.