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Question
Using the method of slope, show that the following points are collinear A (4, 8), B (5, 12), C (9, 28).
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Solution
A (4, 8), B (5, 12), C (9, 28)
Slope of AB = \[\frac{y_2 - y_1}{x_2 - x_1} = \frac{12 - 8}{5 - 4} = \frac{4}{1} = 4\]
Slope of BC =
\[\frac{y_2 - y_1}{x_2 - x_1} = \frac{28 - 12}{9 - 5} = \frac{16}{4} = 4\]
Since, Slope of AB = Slope of BC = 4
Therefore, the given points are collinear.
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