- #1

- 21

- 0

The first three terms of an arithmetic sequence are p, 2p+6, and 5p-12. What is the 4th term of this sequence?

Please explain how to do this.

Arigato!

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter sabanation12
- Start date

- #1

- 21

- 0

The first three terms of an arithmetic sequence are p, 2p+6, and 5p-12. What is the 4th term of this sequence?

Please explain how to do this.

Arigato!

- #2

- 21

- 0

please help me

- #3

- 22

- 0

[tex]p+6=3p-18[/tex]

[tex]2p=24[/tex]

[tex]p=12[/tex]

Only true when p=12. For all other cases it is not an AP.

- #4

- 1,065

- 54

2p-12 <- simplifies to p, of course, if you know p=12

2p+6

5p-12

5p+6

8p-12

8p+6

.

.

.

- #5

- 21

- 0

_{1}-t_{0}=t_{2}-t_{1}and so forth.) In this case [tex](2p+6)-p=5p-12-(2p+6)[/tex]

[tex]p+6=3p-18[/tex]

[tex]2p=24[/tex]

[tex]p=12[/tex]

Only true when p=12. For all other cases it is not an AP.

No I believe you are wrong, it IS an arithmetic sequence. Let me explain...

P does equal 12, and the difference between them is 18, so:

a

Plugging in numbers:

a

so the fourth number is 66

Thanks for your help anyways :)

Share: