Question

If the points A(1,2) O(0,0) and C(a,b) are collinear then.


​

Answer 1

Step-by-step explanation:

Since the given points are collinear, they do not form a triangle, which means

area of the triangle is Zero.

Area of a triangle with vertices (x

1

,y

1

) ; (x

2

,y

2

) and (x

3

,y

3

) is

∣

∣

∣

∣

∣

2

x

1

(y

2

−y

3

)+x

2

(y

3

−y

1

)+x

3

(y

1

−y

2

)

∣

∣

∣

∣

∣

Hence, substituting the points (x

1

,y

1

)=(1,2) ; (x

2

,y

2

)=(0,0) and (x

3

,y

3

)=(a,b)

in the area formula, we get

∣

∣

∣

∣

∣

2

1(0−b)+0(a−1)+a(2−0

∣

∣

∣

∣

∣

=0

=>−b+2a=0

=>2a=b

Answer 2

Answer:

Hope this answer is helpful.