OpenStudy (anonymous):

What is the 43rd term of an arithmetic sequence with a rate of increase of -6 and a11 = 12? HELP ME PLEASE

4 years ago
OpenStudy (solomonzelman):

it is called, common ratio, not rate of increase (but whatever...) Fast way to do it, without finding \(\large\color{black}{ a_1}\). \(\large\color{black}{ a_{43}=a_{11}\times r^{43-11}}\)

4 years ago
OpenStudy (solomonzelman):

plug in your values and solve. IF you have any questions, don't hesitate to ask.

4 years ago
OpenStudy (anonymous):

idk how

4 years ago
OpenStudy (solomonzelman):

ohh, yeah it is arithmetic... -:(

4 years ago
OpenStudy (solomonzelman):

\(\large\color{black}{ a_{43}=a_{11}+ n(43-11)}\) like this.

4 years ago
OpenStudy (anonymous):

what do i put in for a

4 years ago
OpenStudy (solomonzelman):

\(\large\color{black}{ a_{43}=a_{11}+ n(43-11)}\) \(\large\color{black}{ a_{43}=12+(-6)(43-11)}\) \(\large\color{black}{ a_{43}=?}\)

4 years ago
OpenStudy (anonymous):

-180

4 years ago