Pls help its due in half an hour

Common denominator 20

because 4 and 5 can both go into 20 without any remainder

Common denominator 18

because 6 and 9 can both go into 18 without any remainder

Common denominator 8

because 2 and 8 can both go into 8 without any remainder

Hope this was helpful!

b) well because you get well

f(x) is going down by 4

step-by-step explanation:

(its either that or its going left by 4)