Answer:
mid point (x,y) = M (18, 24)
let J (- 4, - 2) be ( x1, y1)
L(a,b) be (x2,y2)
using midpoint formula
(x,y) = [(x1+x2)/2, (y1 + y2)/2]
or, (18, 24) = [(-4+a)/2, (-2+b)/2]
comparing corresponding element we get
18 = (-4+a)/2 24 =(-2+b)/2
or 36 = -4+ a or 48 = -2 +b
or a = 40 or b= 50
L(40,50)