Use FOIL
28x² -8xy +7xy -2y²
28x² -xy -2y²
The answer is y=-8 I’m pretty sure
Answer:
true
Step-by-step explanation:
The answer would be 2,077
You can see how this works by thinking through what's going on.
In the first year the population declines by 3%. So the population at the end of the first year is the starting population (1200) minus the decline: 1200 minus 3% of 1200. 3% of 1200 is the same as .03 * 1200. So the population at the end of the first year is 1200 - .03 * 1200. That can be written as 1200 * (1 - .03), or 1200 * 0.97
What about the second year? The population starts at 1200 * 0.97. It declines by 3% again. But 3% of what??? The decline is based on the population at the beginning of the year, NOT based no the original population. So the decline in the second year is 0.03 * (1200 * 0.97). And just as in the first year, the population at the end of the second year is the population at the beginning of the second year minus the decline in the second year. So that's 1200 * 0.97 - 0.03 * (1200 * 0.97), which is equal to 1200 * 0.97 (1 - 0.03) = 1200 * 0.97 * 0.97 = 1200 * 0.972.
So there's a pattern. If you worked out the third year, you'd see that the population ends up as 1200 * 0.973, and it would keep going like that.
So the population after x years is 1200 * 0.97x
Answer:
The 99% confidence interval for the mean sodium content in Oriental Spice Sauce is between 454.67 milligrams and 1722.61 milligrams
Step-by-step explanation:
We have the standard deviation for the sample, so we use the t-distribution to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 40 - 1 = 39
99% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 39 degrees of freedom(y-axis) and a confidence level of 
. So we have T = 2.7079
The margin of error is:
M = T*s = 2.7079*234.12 = 633.97
In which s is the standard deviation of the sample.
The lower end of the interval is the sample mean subtracted by M. So it is 1088.64 - 633.97 = 454.67 milligrams
The upper end of the interval is the sample mean added to M. So it is 1088.64 + 633.97 = 1722.61 milligrams
The 99% confidence interval for the mean sodium content in Oriental Spice Sauce is between 454.67 milligrams and 1722.61 milligrams
