Question

If A(3,4), B(-4,1) and C(3,a) are collinear, find the value of a ​

Answer 1

Step-by-step explanation:

Let

A(3,4)[x1,y1]

B(-4,1)[x2,y2]

C(3,a)[x3,y3]

so,

ar(∆ABC)= 0 {Collinear}

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

->1[3(1-a)-4(a-4)+3(4-1)]=0

->3-3a-4a+16+9=0

->28=7a

->a=4......

hope u got the answer....