Externally devided... (1 Viewer)

[PoLaRbEaR]

Externally divided...

The point P(7,-1) divides the interval AB externally in the ratio 3:2. If A is (-2,5) find the coordinates of B.

Okay this is how I did it:
ratio = 3:-2
-2(3)-2x = 7
----------
3-2

Is this working out right or wrong? Because I looked at the solutions and it tells me I'm wrong, but my friend says it's right, so I'm not sure....
The solutions say that the ratio is -3:2...how would you know which one is negative?
[From PLC 2002 trial]

 

[redslert]

NO THAT IS WRONG!

when subbing in the points A or B

the second point goes first! ie B

(x)(3)-2(5) = 7
----------
3-2

(y)(3)-2(-2) = -1
----------
3-2

 

[redslert]

the order of the points is EXTREMELY important please go back to your textbooks and do some questions!!!!!