Answer:
The other endpoint is ( -1,15)
Explanation:
21.
The x coordinate of the midpoint is the sum of the x coordinate of the endpoints divided by 2
(-5 +x)/2 = -3
Multiply each side by 2
-5+x = -6
Add 5 to each side
-5+x+5 = -6+5
x = -1
The y coordinate of the midpoint is the sum of the y coordinate of the endpoints divided by 2
(-1 +y)/2 = -8
Multiply each side by 2
-1+y = -16
Add 1 to each side
-1+y+1 = -16+1
y = -15
The other endpoint is ( -1,15)