Answer:
a(n)=60-30n
Explanation:
Equation to use:
a(n) = a(1) + d(n-1)
where a(1) is the first term, d is the common difference between terms, and n is the nth term you are trying to find.
In this case, a(1) is 30, d is -30, and n is just n.
If you plug that into the equation and use the distributive property, you would get: a(n) = 30 -30n + 30.
Adding the two 30's gets you: a(n) = 60 - 30n, which is the solution.