B, a supplementary triangle because it all adds up to 180 degrees.
The average r. of c. of a function f(x) on an interval [a,b] is:
f(b) - f(a)
--------------
b-a
You'll need to apply this to all four of the given functions.
First function: f(x) = x^2 + 3x
a= -2; b= 3
Then the ave. r. of c. for this function on this interval is:
18 - (-2) 20
------------------ = ---------- = 4. y increases by 4 for every unit increase in x.
3-(-2) 5
Do the same thing for the other 3 functions.
Then arrange your four results in descending order (greatest to least).
All of the above easy one
#18 Supplementary means two angles add up to 180 degrees. Angles JHF
#19. Complementary means two angles that add up to 90 degrees. Angles GHF
#20. Adjacent means two angles that have a common side and vortex that's why it does not work.
Hope this helps :)