Find the coordinates of the other endpoint of the​ segment, given its midpoint and one endpoint.​

Question

midpoint ​(-4,21) endpoint ​(-6,16)

Answer 1

Midpoint formula:

To find (xm,ym) between (x1,y1) and (x2,y2)

(xm,ym) = ((x1+x2)/2,(y1+y2)/2)

we are given xm,ym and x2,y2 and need to find x1,y1

(-4,21) = ((x1+-6)/2, (y1+16)/2)

so (x1 - 6)/2 = -4 and

(y1 +16)/2 = 21

solving for x1:

(x1-6)/2 = -4

x1-6 = -8

x1 = -2

solving for y1:

(y1+16)/2 = 21

y1+16 = 42

y1=26

so other endpoint = (-2,26)