WILL GIVE FAN AND MEDAL
Find an equation for the nth term of the arithmetic sequence.

-15, -6, 3, 12, ...

Question

WILL GIVE FAN AND MEDAL
Find an equation for the nth term of the arithmetic sequence.

-15, -6, 3, 12, ...

anonymous · Answer

We know that the equation is increasing by 9 isn't?

anonymous · Answer

Yes

alones · Answer

@jewea just gave you a hint that they all go by nine "12-(9)=3;
3-(9)=-6 

u see??

anonymous · Answer

I understand that part

alones · Answer

okayii so then what u don't understand

alones · Answer

just add till you get on the ninth term i'll help u

anonymous · Answer

an = -15 + 9(n + 1)
 an = -15 x 9(n - 1)
 an = -15 + 9(n + 2)
 an = -15 + 9(n - 1)

these are my answer choices and idk how they got this from the question

alones · Answer

if it's fine with you

anonymous · Answer

Im very confused

alones · Answer

I think the first one cuz it goes 3,12,21,30...
the second one  doesnt' really match the question it goes 0,-135,-270..
#3_12,21....
#4 is RIGHT :)

anonymous · Answer

Thankyou :)