Answer:
soln ,given,
midpoint of CD=M(-2,5)
let,
C(4,7)=(x1,y1)
D(x1,y2)=?
now by using midpoint formula =(x1+x2)/2+(y1+y2)/2
M(-2,5)=( 4+x2)/2+(7+y2)/2
comparing both sides
-2=(4+x2)/2
-4=4+x2
-4-4=x2
threfore,x2= -8
again
5=(7+y2)/2
10=7+y2
therefore,y2=3
thus , the coordinate of D is D(-8,3)
