Points A = (0,5) and B = (10,13) are joined to form line segment AB. If point P = (x,y) divides AB in the ratio 3:1 externally, then what is x + y?

Guest Jan 9, 2020

#1**+1 **

~~The point divides the line into two segments in ratio of 3:1 the point is thus 3/4 from the end. (3 +1 =4) ~~

~~ there are two points (depending on which end of the line you start at ) which will divide the line this way....~~

~~I will assume the point P is furthest away from A~~

~~the x coordinate will be 0 + (10 - 0 ) x 3/4 = 7.5~~

~~the y coordinate will be 5 + (13-5) x 3/4 = 11~~

~~x+y = 18.5~~ Sorry....this was for INTERNAL ratio division

For EXTERNAL ratio of 3:1 m = 3 n = 1

Formula: Y={[(mx2-nx1)/(m-n)],[(my2-ny1)/(m-n)]}

3(10)-(1)(0) / ((3-1) = x_{p} = 15

3(13)-1(5) / (3-1) = y_{p = 17 }

_{Thanx geno for spotting my error ! }

ElectricPavlov Jan 9, 2020