Count over to x = 7 count up to where you intersect the red graph this is h(7) and it equals 5
now count over x = 5 and count to the red line -1 h h(7) = -1
Realize that h(7) is equal to 5. Look at the graph, and we see that indeed, if we count out 7 spots from the origin xwise, the y value that corresponds is 5. As such, if we want to compute h(h(7)), that's equivalent to h(5). We repeat the process for h(5). We count out 5 spots, and we see that the y value that corresponds with 5 is -1, giving us our answer.