# Which sequence matches the recursive formula? a_n = 2a_(n-1) + 5, where a_1 = 5 A) 5, 10, 15, 20, ... B) 5, 15, 35, 75, ... C) 5, 15, 25, 35, ... D) 5, 20, 35, 50, ...

May 10, 2016

B) $5 , 15 , 35 , 75 , \ldots$

#### Explanation:

${a}_{1} = \boldsymbol{5}$

${a}_{2} = 2 {a}_{1} + 5 = 2 \cdot 5 + 5 = \boldsymbol{15}$

${a}_{3} = 2 {a}_{2} + 5 = 2 \cdot 15 + 5 = \boldsymbol{35}$

${a}_{4} = 2 {a}_{3} + 5 = 2 \cdot 35 + 5 = \boldsymbol{75}$