midpoint ​(-2​,​-8), endpoint ​(-1​,-1​)

Answer 1

I assume we are given the midpoint and endpoint and are tasked with finding the other endpoint.

Midpoint Formula:

(x,y) = ( (x1 + x2) / 2, (y1 + y2)/2)

so x = (x1 + x2)/2 and y = (y1 + y2)/2

We are given (x,y) = (-2,-8) and (x2, y2) = (-1,-1)

Substitute those into the equation and solve for (x1,x2)

-2 = (x1 + -1)/2

-4 = x1 + -1

-3 = x1

-8 = (y1 + -1)/2

-16 = y1 + -1

-15 = y1

Other endpoint is (-3,,-15)