Pls asap80 points and brainleist

the graph represents the money collected at the movie theater on saturday. find the domain when the maximum number of people allowed in the movie theater is 30 people.

graph of y equals 2 times x plus 40 with x axis labeled number of people and y axis labeled amount of money

0 ≤ y ≤ 30
40 ≤ x ≤ 100
0 ≤ x ≤ 30
40 ≤ y ≤ 100