Question

1 Verify that the points (1,5).(2.3) and (-2,-1) are collinear .​

Answer 1

find the distance between these points A(1,5) B(2,3) C(-2,-1)

AB^2=(X2-X1)2+(Y2-Y1)2

=(2-1)^2+(3-5)^2

=1+4=5

BC^2=(-2-2)2+(-1-3)2

=(4)2+(4)2

=16+16=32

CA^2=(-2-1)2+(-1-5)2

=(-3)2+(-6)2

9+36=45

AB+BCis not equal to CA

there are not collinear

Answer 2

Answer:

Area of triangle =1/2|X1(Y2-Y3)+X2(Y3-Y1)+X3(Y1-Y2)|

=1/2|1(1-(-3)) +2(-1-1)-2(5-3)|

=1/2|4-4-4|

=1/2|-4|

=1/2×4

=2

So these points ate not collinear