Question

Find the coordinates of the other endpoint when you are given the midpoint (point M) and one of the endpoints (point P)

Answer 1

The known endpoint is P = (-16,0)

Let Q = (x,y) be the other endpoint. It is unknown for now.

Looking at the x coordinates of P and Q, we see that they are -16 and x respectively. Adding these values up gives -16+x. Dividing that result by 2 gives (-16+x)/2. This result is exactly equal to the midpoint x coordinate, which is the x coordinate of M (0). 

So we have this equation (-16+x)/2 = 0. Let's solve for x

(-16+x)/2 = 0
2*(-16+x)/2 = 2*0
-16+x = 0
x-16 = 0
x-16+16 = 0+16
x = 16

Therefore the x coordinate of point Q is 16.

------------------------------------

Let's do something similar for the y coordinates.

The y coordinates of P and Q are 0 and y respectively. Add them up and divided by 2, then set the result equal to -16 (y coordinate of midpoint M) getting this equation (0+y)/2 = -16

Solve for y

(0+y)/2 = -16
y/2 = -16
2*y/2 = 2*(-16)
y = -32

The y coordinate of point Q is -32

------------------------------------

The point Q goes from (x,y) to (16, -32)

Final Answer: (16, -32)