Ihave homework and i dont understand it its called "solving systems of equations by elimination." the problem im stuck on is< br />
8x+y=-16< br />
-3x+y=-5< br />
i need the answer and how to do it.

Is the product of seventeen negative numbers, positive or negative ?

Describe in detail how you would construct a 95% confidence interval for a set of 30 data points whose mean is 20 and population standard deviation is 3. be sure to show that you know the formula and how to plug into it. also, clearly state the margin of error.

You use math in day-to-day routines when grocery shopping, going to the bank or mall, and while cooking. how do you imagine you will use math in your healthcare career?