Respuesta :

Answer:

The 54th term is -855

Step-by-step explanation:

Since the sequence is arithmetic, then we have to use the rule of the nth term

[tex]a_{n}=a+(n-1)d[/tex]

a is the first term

d is the common difference

n is the position

The given sequence is -7, -23, -39

a=-7

d=-23-(-7)=-23+6=-16

We need to find the 54th term

n=54

Substitute them in the rule

[tex]a_{54}=-7+(54-10)(-16) [/tex]

Solve it:

[tex]a_{54}=-7+(53)(-16)\\ a_{54}=-7-848\\ a_{54}=-855 [/tex]

The 54th term is -855

Answer:

The characteristic of an arithmetic sequence is:

  • The difference between the consecutive terms is constant.

This difference between consecutive terms is called common difference and is denoted by (d)

STEP I

(finding the common difference)

As stated above, the common difference is the difference between consecutive terms and, thus, will be found out by subtracting any two consecutive terms.

-7 and -23 are two consecutive terms in the sequence!

Subtracting (-7) from (-23):

[tex] \implies \mathsf{d = - 23 - ( - 7)}[/tex]

[tex] \implies \mathsf{d = - 23 + 7}[/tex]

[tex] \implies \mathsf{ \underline{d = -16}}[/tex]

STEP II

(Finding the nth term)

The formula used for finding the nth term of an arithmetic sequence is:

[tex] \boxed{ \mathsf{a _{n} = a + (n - 1)d }}[/tex]

Here,

  • [tex]a_n[/tex] = nth term
  • a = first term
  • d = common difference

The question asks us to find the 54th term of the sequence.

Substituting 54 for n:

[tex] \implies \mathsf{a _{54} = a + (54 - 1)d }[/tex]

  • The first term of the sequence is -7

substituting -7 for a and -16 for d

[tex] \implies \mathsf{a _{54} = - 7+ (54 - 1)( - 16)}[/tex]

[tex] \implies \mathsf{a _{54} = - 7+ (53)( - 16)}[/tex]

[tex] \implies \mathsf{a _{54} = - 7 - 848}[/tex]

[tex] \implies \mathsf{ \underline{a _{54} = - 855}}[/tex]

ANSWER:

The 54th term of the sequence is -855.

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Learn more about nth term of an AP here:

https://brainly.com/question/16613594

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Hope this helps!