Answer:
Shewannameetcarti answered the numbers 6 and 7 perfectly!
I'll just add on with number 8.
a. 4 + 12x
(This is because the first figure starts with 4 toothpicks, and each time there
are 12 more toothpicks in the pattern.)
b. *graphs are attached; both are the same equation, one is just zoomed out
c. Using the graph, the number of toothpicks in figure 7 is 88 toothpicks.
Substitute 7 for x: 4 + 12(7) = 88