Question

Write an equation for the nth term of the arithmetic seqeuence. Then find a10-

-6,-9, -12,-15, ...
an
11
a10

Answer 1

Given- A sequence as -6,-9,-12,-15

To find- The equation for the nth term of the arithmetic sequence and to find the value of
`a_(10)`.

Explanation- The common difference is
`-9-(-6)=-3`

We know the arithmetic sequence formula is

`a_n=a_1+(n-1)d\\a_n=-6+(n-1)(-3)`

When n=10

`a_(10)=-6+(10-1)(-3)\\a_(10)=-6+9(-3)\\a_(10)=-6-27\\a_(10)=-33`

Final answer- The value of 10th term is -33.