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3 years ago

What is the 20th term of the arithmetic sequence?

Mathematics

2 answers:

podryga [215]3 years ago

8 0

You just need to substitute 20 for x and then solve.

a(20) = -5 +(20-1)3

Simplify: a(20) = -5 + (60-3)

Simplify: a(20) = -5 + 57

Result: a(20) = 52

So, 52 is the 20th term of the arithmetic sequence.

Mandarinka [93]3 years ago

8 0

In the equation
$a(n) = - 5 + (n - 1)3$
Let n=20 and evaluate it as:

$a(20) = - 5 + (20 - 1)3 \\ \\ a(20) = - 5 + (19)3 \\ \\ a(20) = - 5 + 57 \\ \\ a(20) = 52$

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Given:

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omeli [17]

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The explanation is shown below:

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2. Substitute values:

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