Answer:
1 unit
Step-by-step explanation:
If point J is the midpoint of segment FG with endpoints F(1,4) and G(5,12), then its coordinates are

If point K is the midpoint of segment GH with endpoints G(5,12) and H(-1,4), then its coordinates are

The measure of JK is

Its not the whole problem :{
2x-4y=-16
ax+4y=6 +
--------------------
2x+ax=-10; for x=-2,
2(-2)+a(-2)=-10
-2a=-10+4
a=-6/-2
a=3
I know step 5 is (x-2)(x+2)(x+1)
But I don't know what step 4 is.
Im stuck.