Arithmetic Sequences Problem

*"Find three consecutive terms of an arithmetic sequence if their sum is 3 and their product is -15"*

I know the answer is -3,1,5 but I pretty much just guessed that on a fluke. What is the method of answering this question? I don't think I'll get the marks unless I use a method of some sort :(

Re: Arithmetic Sequences Problem

Let $\displaystyle a$, $\displaystyle (a+d)$, and $\displaystyle (a+2d)$ be the three consecutive terms, where $\displaystyle d$ is the common difference. Set up simultaneous equations for $\displaystyle a$ and $\displaystyle d$.

Re: Arithmetic Sequences Problem

Quote:

Originally Posted by

**Quacky** Let $\displaystyle a$, $\displaystyle (a+d)$, and $\displaystyle (a+2d)$ be the three consecutive terms, where $\displaystyle d$ is the common difference. Set up simultaneous equations for $\displaystyle a$ and $\displaystyle d$.

Thanks! It makes sense now :)