Respuesta :

Answer:

p=-11

Step-by-step explanation:

if they are colinear,

p-1/1--5 = -2-p/4-1

cross multiple

(p-1)(4-1)=(1--5)(-2-p)

(p-1)×3 =-4(-2-p)

3p-3 = 8+4p

p= -3-8

p=-11