Answer:

Step-by-step explanation:
Given


Required
The explicit formula
First, calculate 
Set n=2; So:


Substitute -25 for 


Calculate the common difference (d)



So, the nth term is:


Open bracket

Collect like terms


Answer:
Step-by-step explanation:
F(x) = 7 - 5x + 7x²
f(-9) = 7 - 5*(-9) + 7*(-9)²
= 7 + 45 + 7*81
= 7 + 45 + 567
= 619
90
-12. The newsstand had 90 copies at the beginning of the day
===
78
Answer:
-30 i guess
Step-by-step explanation:
When presented with a box plot, it is better to identify the 5 numbers that are important in the box plot.
5 number summary of the boxplot.
1) minimum number - 16
2) 1st quartile - 21
3) 2nd quartile or median - 26
4) 3rd quartile - 29
5) maximum number - 34
Range is the difference of the maximum value from the minimum value of the data set.
Interquartile range is the difference of the 3rd quartile from the 1st quartile.
Range: 34 - 16 = 18
IQR: 29 - 21 = 7