1966yenko 1966yenko 22-12-2020 Mathematics contestada Given the Arithmetic Sequence 9,12,15,18,21,...find the formula 1. A(n)=3+(n-1)9 2. A(n)=9+(n-1)3 3. A(n)=21+(n-1)9 4. A(n)=9+(n-1)21
