Here we want to find the equation of the line containing the median CP.
P, being the midpoint of AB can be found using the midpoint formula as:

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The slope m of the line through CP can be found by the slope formula using points C(18, -8) and P(0, 1):

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Now, we can write the equation of the line with slope -1/2, passing through
P(0, 1):

.
Answer:
The answer for number A would be 1/3
The expression to find the number of notebooks James bought would be written as:
Number of notebooks = total spent / cost per item
Number of notebooks = (2y^2 + 6) / <span>(y^2 − 1)
</span><span>If y = 3, then the number of notebooks bought would be:
</span>Number of notebooks = (2y^2 + 6) / (y^2 − 1)
Number of notebooks = (2(3)^2 + 6) / (3^2 − 1)
Number of notebooks = 3 pieces<span>
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