What a17 for the following arithmetic sequence

Question

Find a17 for the following arithmetic sequence

-5,-12,-19

algebra two

Answer 1

a_n=a₁+(n-1)d

a_n=the nᵗʰ term in the sequence

a₁=the first term in the sequence

d=the common difference between terms

a₁=-5

d=-7

a_n=-5+(n-1)(-7)

a₁₇=-5+(17-1)(-7)

a₁₇=-117

Answer 2

Hi Brooke,

-5,-12,-19,.....

First recognize r HOW?

-12 -(-5) = -12 + 5 = -7 be careful -19 - (-12) -19 + 12 = -7 must be the same

r = -7

Second, general form a_n = a₁ + ( n - 1 ) r

a₁₇ = -5 + ( 17 - 1 ) * (-7) = -117

a₁₇ = -5 + 16 * (-7) = -117

I hope it is useful,

Minoo

Answer 3

a₁₇ = -5(17 - 1)(-7)