Kis the midpoint of line jl. j has coordinates (2, -1), and k has coordinates (-4, 3). what are the coordinates of l?

Well the midpoint formula to find the coordinates is ( (x₂ + x₁)/2 , (y₂ -+ y₁)/2 )
Basically you find the average of each points to find the midpoint. Well we already have the midpoint so  we plug our numbers in with variables to find the other point. Let's start with the x value of coordinate L:
(2 + x₁)/2 = -4    the 2 came from point J and the -4 came from the midpoint k.
2+ x₁ = -8
x₁ = -10        this is the  x coordinate of point L. Let's find the y
(-1 + y₁)/2 = 3
-1 + y₁ = 6
y₁ = 7      this is the y coordinate of L
L's coordinate is (-10, 7)