MediumMathematicsHigh School (11–12)Coordinate Geometry › Straight LinesNumerical

Find k so that A(2, 5), B(k, 9) and C(8, 17) lie on one straight line…

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Find $k$ so that $A(2, 5)$ , $B(k, 9)$ and $C(8, 17)$ lie on one straight line. Then find the slope of that line.

Need a reminder? The key ideaShow

Lines with slopes $m_1$ and $m_2$ are parallel when $m_1 = m_2$ and perpendicular when $m_1 m_2 = -1$ . Three points are collinear when the slope of the first pair equals the slope of the second pair.

The worked solution

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Find k so that A(2, 5), B(k, 9) and C(8, 17) lie on one straight line…

The worked solution

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