Answer:
Step-by-step explanation:
The degree of the function is odd, so the ends tend in opposite directions. The leading coefficient is negative, so the right end (as x gets large) will tend toward -∞. Then the left end tends toward +∞.
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If the degree is even, both ends tend in the same direction. That direction matches the sign of the leading coefficient.
Answer:
Step-by-step explanation:
Perhaps you want to use the points (t, P) = (4, 150) and (6, 160) to find the parameters P0 and k in the equation ...

We know from the given points that we can write the equation as ...

Comparing this to the desired form, we see that ...

So, the approximate equation for P is ...

And the parameters of interest are ...
For margin of error to be a maximum of 3:
3 = z*(SD / sqrt(n)), where z is the z-score, SD is the standard deviation and n is the sample size.
z = 1.96 for a 95% confidence interval, and we are given SD = 15.
3 = 1.96*15/sqrt(n)
sqrt(n) = 9.8
n = 96.04 ~ 96 commercials.
4X-4Y>28
X-Y>7 both side divide by 4