1. Midpoint = (-2+12)/2 = 10/2 = 5
2. C(5, 2) E(-1, 0) D=?
[tex]x_E= \frac{x_C+x_D}{2} \ \ \ \to \\\\ -1= \frac{5+x_D}{2} \ \ \ \to \ \ \ -2=5+x_D \ \ \to \ \ x_D=-2-5=-7
\\\\\\y_E= \frac{y_C+y_D}{2} \ \ \ \to \\\\ 0= \frac{2+y_D}{2} \ \ \ \to \ \ \ 0=2+y_D \ \ \to \ \ y_D=0-2=-2[/tex]
Answer: D(-7, -2)