Question

If the point A(-3,9),B(a,b),C(4,-5) ,are collinear and a+b=1,then find the value of a and b.

Answer 1

Step-by-step explanation:

given a+b=1

a=1-b........(i)

1/2[(-3)(b+5)+a(-5-9)+4(9-b)]=0

1/2[-3b-15-14a+36-4b]=0

1/2[-14a-7b+21]=0

7/2[-2a-b+3]=0

7/2[-2(1-b)+3]=0

-2+2b+3=0

2b=-1

b=-1/2

a=1+1/2

a=3/2