Saturday

January 24, 2015

January 24, 2015

Posted by **Anonymous** on Saturday, March 29, 2008 at 4:42pm.

Using vectors, demonstrate that the three points A(5, -1), B(-3,4) and C(13,-6) are collinear.

Solution

AB = (-8, 5)

BC = (16, -10)

Then BC = 2AB

AB and BC have the opposite direction, so the points A, B, and C must be collinear.

I don't understand how AB = (-8, 5) and

BC = (16, -10)

- Math - explanation -
**Damon**, Saturday, March 29, 2008 at 5:35pmvector AB is (-3 -5) i + (4 - (-1) ) j

= -8 i + 5 j

vector BC is (13 - (-3)) i + (-6 - 4) j

= 16 i - 10 j

- Math - explanation -
**Damon**, Saturday, March 29, 2008 at 5:37pmNow the lines are collinear because they go through the same point (point B)

and they have the same slope (although one is going down the hill while the other goes up)

- Math - explanation -
**Amanda**, Saturday, March 29, 2008 at 5:38pmI'm not sur if this will help, but to get AB, you subtract A from B and B from C.

B(-3x,4y)-A(5x,-1y)=x(-3-5),y(4+1)=

AB(-8,5)

C(13x,-6y)-B(-3x,4y)=x(13+3),y(-6-4)=

BC(16,-10)

**Answer this Question**

**Related Questions**

Math: Vectors - Collinear - Can you please check whether my answers are correct...

geometry - Please help me to draw this figure four points that are not collinear...

math - My son has been given the collinear problem below that has be stumped two...

Mamthematics - Vectors - a) If vector u and vector v are non-collinear vectors ...

math - There are nine points on a piece of paper. No three of the points are ...

Math - Rewrite the following definition as a biconditional: Points that lie on ...

Math - Three points D, E, and F are collinear. Is there only one plane that ...

Math - Given two non-collinear vectors a and b, show that a, axb, and (axb)xa ...

math - Are three collinear points are always also coplanar points.

math - suppose n points are in space, no three are collinear and no four or are ...