Answer:
a; d = 20n
Explanation:
you can use the process of elimination and an example problem to help!
so if mason mowed 2 lawns, he'd make $40, right? now you could try each equation to see which one equals $40
a. d = 20(2) ⇒ d = 40
b. n = 20d ⇒ 2 = 20d ⇒ d = 0.1
c. d = 20 ÷ n ⇒ d = 10
d. n = 20 + d ⇒ 2 = 20 + d ⇒ d = -18
therefore, your answer would be A!