What is the sum of the first 14 terms of the sequence an = 6n -12

1 answer:

6 0

When n = 1 first term = -6
n = 2 second term = 0
n = 3 third term = 6

n = 4 4th term = 12

so we have an Arithmetic sequence first term = -6 and common difference = 6

Sum 14 terms = (14/2)[2*-6 + (14-1)*6]

= 462 answer

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Answer:

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Step-by-step explanation:

Let the length of the rectangle be a.

Given that, its width is 5 in less than the length.

So,

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First, let's find the area of the rectangle.

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