Question

15 POINTS !!!!

Answer 1

Answer:

$a_n=7.51+0.35(n-1)$

Step-by-step explanation:

Formula of nth term = $a_n=a+(n-1)d$

We are given that  an is the foot length in inches that corresponds to a shoe size of n.

We are given that A men’s size 9 fits a foot 10.31 inches long

So, n = 9

$a_n = 10.31$

Substitute the values in the formula :

So, $10.31=a+(9-1)d$

$10.31=a+8d$ ---1

We are given that a men’s size 13 fits a foot 11.71 inches long.

So, n = 13

$a_n = 11.71$

Substitute the values in the formula :

So, $11.71=a+(13-1)d$

$11.71=a+12d$ ---2

Subtract 1 form 2

$11.71-10.31=a+12d-a-8d$

$1.4=4d$

$\frac{1.4}{4}=d$

$0.35=d$

Substitute the value of d in 1

$10.31=a+8(0.35)$

$10.31-8(0.35)=a$

$7.51=a$

Substitute the value of a and d in formula given above

$a_n=7.51+(n-1)0.35$

So, the explicit formula for the arithmetic sequence is $a_n=7.51+0.35(n-1)$

Answer 2

So the answer would be A. I had a bit of trouble figuring this out, but then I went to Order of Operations and found it out. 

So you fill in n, and I just used 9 since it's in the question. So then, subtract 1 from 9, giving you 8. Then you multiply 0.35 by 8, giving you 2.8. Now lastly, add 7.51, and you get 10.31

I hope this helps you! If it does, please rate as Brainliest :D