let X, Y, and Z be points such that XZ/XY = ZY/XY = 1/2 . if Y= (1, 7) , Z= (-1, -7), then what is the sum of the coordinates of X?

Guest Apr 26, 2019

#1**+2 **

If XZ/XY = ZY/XY = 1/2

Then XZ = ZY

Then Z must be the midpoint of XY

So

[ 1 + x coord of X ] / 2 = -1 multiply through by 2

1 + x coord of X = -2 subtract 1 from both sides

x coord of X = - 3

And

[ 7 + y coord of X ] / 2 = -7

7 + y coord of Y = -14 subtract 7 from both sides

y coord of Y = -21

So X = (-3, -21) and the sum of the coordinates = -24

CPhill Apr 26, 2019