Question

for what value of p are the points (1,1) (3,p) (-1,4) collinear

Answer 1

Answer:

The given points are A(2 ,1) ,B(p , -1) and C(-1,3). These points are collinear if sloe of AB and BC is same. Therefore the required value of p is 5.

Answer 2

p = - 2 *

Step-by-step explanation:

three points are collinear if area of ∆ formed by these three points = 0

1/2 * [x1( y2-y3) + x2(y3-y1) + x3(y1-y2)]= 0

1(p-4) + 3(4 - 1) + (-1){1 - p) = 0 × 2

p - 4 + 9 - 1 + p = 0 => 2p = - 4 => p = - 2