What is the first term of a 10-term arithmetic sequence where t2=10 and S=120

Question

Not sure how to do this one, Thanks!

Answer 1

t2=10     --> t₁+d=10 (d is the common difference)

S₁₀=120 -->

(t₁+t₁₀)(10/2)=120

t₁+t₁+9d=24

2t₁+9d=24

So, you have to solve

t₁+d=10

2t₁+9d=24