Question

Find the value of b for which the points A (1;2) ;B (_1;b) ; C (_3;_4) are collinear

Answer 1

Answer:

-0.4

Step-by-step explanation:

Since A, B and C are collinear, we have,

slope of AB = slope of AC

i.e, $\frac{b-2}{-1-1} = \frac{-4-2}{-3-2} \\\\\frac{b-2}{-2} = \frac{-6}{-5} = \frac{6}{5}\\5b - 10 = -12\\5 b = -2b = \frac{-2}{5} = -0.4$