Answer:
18.5
Explanation:
It says
IJ is the midsegment of the triangle. So it divides both adjacent sides in half/at modpoint.
so HF is 10 cm .. half of that is 5 cm
GH is 13 cm.. Half of that is 6.5 cm
now we have IJ = 7 cm given
add all those.. you get 18.5 cm