Question 1 Report
Given that (5, 2), (-4, k) and (2, 1) lie on a straight line, find the value of k.
Three points are collinear when the slope between any two pairs is the same.
Using \((5,2)\) and \((2,1)\): \[ m = \frac{2-1}{5-2} = \frac{1}{3}. \]
Using \((2,1)\) and \((-4,k)\) and equating the slope: \[ \frac{k-1}{-4-2} = \frac{1}{3} \Rightarrow \frac{k-1}{-6} = \frac{1}{3}. \]
\[ k - 1 = -2 \Rightarrow k = -1. \]
Everything you need to excel in your exams