Answer:
Part 1) 

Part 2) 

Part 3) 

Part 4) 

Explanation:
Part 1) HI = 3.9 and HJ = 6.2. Find IJ
we have that
I is between H and J

substitute the given values and solve for IJ

subtract 3.9 both sides
 

 

Rewrite

Part 2) JI = 25 and HI = 13. Find HJ 
we have that
H is between I and J

remember that
IH=HI and IJ=JI
substitute the given values and solve for HJ

subtract 13 both sides


Rewrite

Part 3) H is the midpoint of IJ and IH = 0.75. Find HJ
we have that
H is between I and J and H is the midpoint of IJ
so

 ----> because H is the midpoint
we have

therefore

Part 4) H is the midpoint of IJ and IJ = 9.4. Find IH
we have that
H is between I and J and H is the midpoint of IJ
so
 -----> equation A
 ----> equation B
substitute equation B in equation A

substitute the given value and solve for IH

Divide by 2 both sides
