## teller one year ago Can someone help me to see if I got this right ?

1. jim_thompson5910

2. teller

3. teller

I just posted it

4. jim_thompson5910

ok one moment

5. teller

The help video they just gave me doesn't even tell us how to even do that kind problem it's everything else but those kind of problems

6. teller

I know it's going to be 1 but I can't just put 1

7. jim_thompson5910

are you familiar with finding the slope?

8. teller

Not asking for the slope though and no.

9. jim_thompson5910

well with finding any linear function, you find the slope first

10. jim_thompson5910

all linear equations are in the form y = mx+b m = slope b = y intercept

11. teller

See the video didn't say that...

12. jim_thompson5910

what is the video saying (summarize it the best you can)

13. teller

It was in the help section when I clicked it and it's input output tables and she just shows you how to find the missing numbers nothing about what in my work this is the video https://www.youtube.com/watch?v=y_aaOS6Q2qo

14. jim_thompson5910

ok let me watch it

15. teller

Frustrates me that they play students like this .They link a video and it's nothing on the problems about how to find N or anything like that ...

16. jim_thompson5910

A big vague how she says "the rule is 3" at 41 seconds

17. teller

Yea but when I do what she does it tells me I'm wrong on almost every single one I have to use those signs that you see on the right hand side of the picture.

18. jim_thompson5910

ok so the video doesn't help with finding the nth term

19. teller

That's what I said lol

20. jim_thompson5910

yeah I'm just confirming. Anyways, as the inputs increase by 1, what's going on with the outputs?

21. teller

its decreasing

22. jim_thompson5910

by how much?

23. teller

By 1 so the answer is going to be 1

24. teller

I want to put 1-n-1 but I can't or 1xn-1

25. jim_thompson5910

the x values (the inputs) are increasing by 1 the y values (the outputs) are decreasing by 1 (so we say -1) the slope is equal to the change in y over the change in x $\Large \text{Slope} = \frac{\text{change in y}}{\text{change in x}}$ $\Large \text{Slope} = \frac{-1}{1}$ $\Large \text{Slope} = -1$ make sense?

26. teller

so it would be -1 over 1?

27. jim_thompson5910

yes which reduces to -1

28. teller

so the final answer is -1 over 1 - 1? or just -1 over 1

29. jim_thompson5910

-1 is just part of the answer

30. jim_thompson5910

m = -1 is our slope. It tells us how things are changing

31. jim_thompson5910

pick any pair of input and output values say x = 1 and y = 5 we will plug m = -1, x = 1 and y = 5 into y = mx+b and solve for b

32. jim_thompson5910

y = mx+b y = -1*x+b ... replace m with -1 y = -1*1+b ... replace x with 1 5 = -1*1+b ... replace y with 5 now solve for b

33. teller

6?

34. jim_thompson5910

yep

35. jim_thompson5910

m = -1 and b = 6 so y = mx+b turns into y = -1*x + 6 which is simplified to y = -x+6

36. jim_thompson5910

now if you replace the x with n (changing variables is perfectly valid) we go from -x+6 to -n+6

37. teller

so the final answer is -n+6?

38. jim_thompson5910

so the nth term is -n+6 example: replace n with 4 and you'll get -n+6=-4+6 = 2 which is exactly the output for the input of 4

39. jim_thompson5910

correct

40. teller

Thank you!

41. jim_thompson5910

you're welcome