## ayeeeitskateee one year ago Write an equation of the line, in point-slope form, that passes through the two points (-2, 15) and (9, -18) Please explain this to me so I can jot it down in my notebook for future reference. Will medal/fan as always.

• This Question is Open
1. pooja195

Find the slope first $\LARGE \frac{y_2-y_1}{x_2-x_1}=slope$

2. pooja195

If you need help finding the slope let me know.

3. ayeeeitskateee

Hold on. Let me write it. :)

4. pooja195

:) ok

5. ayeeeitskateee

18+15 over 9-2?

6. ayeeeitskateee

-18, sorry.

7. ayeeeitskateee

-3/7 is what I got.

8. ayeeeitskateee

The book gives me these answer choices and I'm totally not sure. y-2=-3(x-15) y-2=-1/3(x+15) y-15=-3(x+2) y-15=-1/3(x+2) What does the x+ a number mean? :(

9. pooja195

$\LARGE \frac{-18-15}{9--2}=slope$ $\LARGE \frac{-18-15}{9+2}=\frac{- 3 }{ 11 }$

10. ayeeeitskateee

Oh. - 15. I did +15.

11. pooja195

Well a negative + negative makes the plus sign its just 15 not -15 so its just -3 same thing with the bottom it was 9--2 right? so i just added the 2 to get 11

12. pooja195

Next step $\huge y-y_1=m(x-x_1)$ where m=slope (x1,y1)

13. ayeeeitskateee

I understand how the formula goes. I just haven't used it in a few years. lol. But thank you for refreshing my memory. Anyways, I got y-15=-3/11(x-2) and that's not a choice. :( Is there another step?

14. pooja195

15. ayeeeitskateee

I have already said them above. Let me copy paste. :)

16. ayeeeitskateee

The book gives me these answer choices and I'm totally not sure. y-2=-3(x-15) y-2=-1/3(x+15) y-15=-3(x+2) y-15=-1/3(x+2) What does the x+ a number mean? :( thats what I said. My choices are those 4.

17. pooja195

Like i said before the 2 is a negative 2 if two negative signs are next to each other they become postivie

18. ayeeeitskateee

Okay, what about the slope? It doesnt match up.. or maybe I just suck at math. lol.

19. pooja195

$$\color{#0cbb34}{\text{Originally Posted by}}$$ @ayeeeitskateee I understand how the formula goes. I just haven't used it in a few years. lol. But thank you for refreshing my memory. Anyways, I got y-15=-3/11(x-2) and that's not a choice. :( Is there another step? $$\color{#0cbb34}{\text{End of Quote}}$$ $\huge~\rm~y-15=-3/11(x-2)$ $\huge~\rm~y-15=-3/11(x-(\huge\color{red}{-}2)$

20. pooja195

Ok lets redo the slope hold on $\LARGE \frac{-18-15}{9--2}=slope$ $\LARGE \frac{-18-15}{9+2}=\frac{- 33 }{ 11 }$

21. pooja195

We can simplfy the slope (we made a mistake earlier -18-15=-33 not -3 )

22. ayeeeitskateee

-3?

23. ayeeeitskateee

for the slope?

24. pooja195

Yep

25. pooja195

26. ayeeeitskateee

C. :)

27. ayeeeitskateee

y-15=-3(x+2)

28. pooja195

Well done :)

29. ayeeeitskateee

Thank you so much. it's rare somebody can help as much as you did!!

30. pooja195

awee :') thanks let me know if you need more help! :D

31. ayeeeitskateee

Will do. :)