The formula for any arithmetic sequence is an = a1 + d(n - 1), where an represents the value of the nth term, a1 represents the value of the first term, d represents the common difference, and n represents the term number. What is the formula for the sequence -15, -11, -7, ...? an = -15 + (-4)(n - 1) an = -15 + (n - 1) an = 4 + (-15)(n - 1) an = -15 + 4(n - 1)

The 4th choice

Step-by-step explanation:

    To figure this out you would have to just lug in all of the numbers into the equation to find the correct answer.

    So first we would plug in the first number for a1 which will be -15. Then we would put in d or the common difference (the number of numbers in between the 2 numbers). So d in this case would be positive 4 since every single time the number is being added to 4.

    Now we can solve, so we would just find all of the choices that do not have  +4 because that will be wrong. Automatically you can see that choices 1 and 2 are wrong and 3 also looks wrong and the only one that matched our formula is 4 and 4 is the correct answer.

step-by-step explanation:

given perimeter: 28cm

length: 9cm

atp,

2(l+w)=p of the reactangle

2(9+x)=28

18+2x=28

2x=28-18

x=10/2

x=5

therefore width is 5 cm

median is the value separating the higher half of a data sample, a population or probablity distribution from the lower half.

step-by-step explanation:

say you have 3,8,7,3,1,9,8 order them from lowest to highest

if orderd it would be 1,3,3,7,8,8,9 now you take away from the lowest and the highest until you end up in the middle.

so you would remove the 1 and 9 leaving you with 5 digits remaining

when you've reached the middle that would be your answer so in this case the answer is 7

if there were two numbers left say 7 and 5 you'd and them together so 12 then divide by 2 witch would equal 6 so the answer would be 6

good luck on that project hoped i you at all