Hi. Please explain to me how to do these three problems:(adsbygoogle = window.adsbygoogle || []).push({});

1. The terms x+3, 3x-1, and 7x-2 are consecutive terms in an arithmetic sequence. Find x.

2. The sum of the first twenty-eight terms of an arithmetic series if the sum of the first twelve terms is -72 and the sum of the first twenty-four terms is 144.

3. Find a, d, and tn for this sequence: t4= -9 , t15 = -31

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# Homework Help: Arithmetic Sequence Series Problem

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