Answer:
83
Step-by-step explanation:
a_1 = -4
a_2 = -1
a_2 - a1 = -1 - (-4) = 3
Each new term is 3 added to the previous term.
a_n = a_1 + 3(n - 1)
Test: Let's find the 4th term and see if we get a_4 = 5.
a_4 = a_1 + 3(4 - 1) = -4 + 3(3) = -4 + 9 = 5
We see that the 4th term really is equal to 5.
a_30 = a_1 + 3(30 - 1) = -4 + 3(29) = -4 + 87 = 83
