If the points (–1,2,–3),(4,a,1) and (b,8,5) are collinear, then a and b are respectively equal to
5 and 5
9 and 5
5 and 9
-5 and 9
Step1: Find AB→ and AC→
Let the given points be A-1,2,-3,B4,a,1 and Cb,8,5
AB→=4--1,a-2,1--3=5,a-2,4
Since, the points are collinear.
x2-x1=x3-x2,y2-y1=y3-y2
=> b-4=4-(-1) and a-2=8-a
=> b=9 and 2a=10
=> a=5 and b=9
Hence, option (3) is correct.
If the points A (-1, -4), B (b,c) and C (5, -1) are collinear and 2b + c =4, find the values of b and c.
If the points (–1,2,–3),(4,a,1) and (b,8,5)are collinear, then a andb are respectively equal to