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I have some maths homework due in on monday, therefore I can't ask my teacher for help and the three equations I have are a bit more advanced than what sir taught us. Here is the question I'm stuck on:

$$ y \leq 3y + 2 \leq 8 + 2y $$

I would appreciate it if someone could give me a solution and/or explanation of it please. That way I don't consider it to be cheating, as I am learning not just copying!

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You did not state a question. – Raphael Jan 15 '11 at 19:04
up vote 6 down vote accepted

$a\leq b\leq c$ just means $a\leq b$ AND $b\leq c$. If you solve both of these individual inequalities, then the solution to the original problem is the intersection of their solution sets . Therefore I recommend starting by solving each of $y\leq 3y+2$ and $3y+2\leq 8+2y$.

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Hi, thank for your answers everyone. I just wanted to make sure I worked the answer out right. I got that y >= -1 <= 6 ? – Andy Jan 14 '11 at 19:17
@Andy: You should write $-1\le y\le 6$ – Américo Tavares Jan 14 '11 at 19:36
And just to make it clear, $-1 \leq y \leq 6$ is indeed the right answer. – Oscar Cunningham Jan 14 '11 at 19:41

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