## sammietaygreen 2 years ago help

1. sammietaygreen

@jim_thompson5910

2. jim_thompson5910

What is the slope of the given line?

3. sammietaygreen

Sorry, huh?

4. jim_thompson5910

The given line, can you tell me what the slope is of it

5. jim_thompson5910

What is the slope of y + 2 = 1/3(x - 5)

6. sammietaygreen

one sec let me see

7. jim_thompson5910

If you're not sure, the slope of y - y1 = m(x - x1) is m

8. ParthKohli

Another alternative: The slope of \(y = mx + b\) is \(m\).

9. sammietaygreen

so would it be 1/3?

10. skullpatrol

In the slope-intercept form: y = mx + b you should know the slope of the line is the coefficient m of the x term, right?

11. jim_thompson5910

yep, the slope is 1/3 The slope of ANY perpendicular line is -3/1 (flip the fraction and flip the sign)

12. jim_thompson5910

-3/1 reduces to -3, so that means that the answer is either choice A or B this is because choice A and B have slopes of -3

13. skullpatrol

Where flip the fraction means find the reciprocal and flip the sign means use the opposite sign.

14. sammietaygreen

yes! I remembered that!! Alright how do we know between a and b though?

15. jim_thompson5910

Now use this to find the value of b in y = mx+b y = mx+b y = -3x + b .. plug in m = -3 (the perpendicular slope) 3 = -3(-4) + b ... plug in x = -4 and y = 3 3 = 12 + b Keep going to solve for b

16. sammietaygreen

b = 4?

17. jim_thompson5910

3 = 12 + b 3 - 12 = 12 + b - 12 -9 = b b = -9

18. jim_thompson5910

not sure how you got b = 4

19. jim_thompson5910

y = mx+b y = -3x + b .. plug in m = -3 y = -3x - 9 ... plug in b = -9 So that's your perpendicular equation

20. sammietaygreen

woah! haha I have no idea either...is it b?

21. sammietaygreen

yeah, that's what I got too. thanks!

22. jim_thompson5910

ok great, just a silly math error then I guess