A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

YanaSidlinskiy

  • one year ago

Write the equation of the line which has a slope of 8/9 and passes through (7,-6). Write the answer in slope -intercept form. @e.mccormick

  • This Question is Closed
  1. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    I got some whacky answer such as: y=8/9x-1 This is wrong and I need some help.

  2. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    OK. so, y=mx+b You have an (x,y) and are given an m. So you need to find b. You did that?

  3. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Well, my first step was in doing this: y-(-6) = 8/9(x+7)

  4. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    From there I went: y+6= 8/9x+ umm...I did some weird thing like I subtracted 6 from the 7.. I hate fractions and I don't know how to solve it.

  5. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    It is multiplication. The fraction times the fraction. \(-6=\dfrac{8}{9}7+b\) is also \(-6=\dfrac{8}{9}\cdot\dfrac{7}{1}+b\)

  6. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Once you have that, you need to get all the # on one side and the b on the other... which means ether getting everything into ninths, or knowing how to work with mixed numbers.

  7. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ok, I'll see what I can do. Can I just like multiply straight across?

  8. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    For that 7/1, yes.

  9. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    All numbers are fractions. The 1 just hides.

  10. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yeah, I knew that. I got a mixed number: 6 2/9

  11. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Is there a way to like work without these fractions?

  12. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Not really, but fractions are your friend!

  13. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Yes, definitely....

  14. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    OK, so, as a mixed number, what would you get if you then move those over to not be with the b?

  15. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Subtract?

  16. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yes. You have to subtract it from both sides.

  17. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    So wait. The equation that I have right now is: -6= 8/9x + 6 2/9 Is that correct? I want to know before we actually move on...

  18. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    No. You dealth with the 8/9x, you do not know the b. -6 = 6 2/9 + b

  19. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    See, you replaced the m, x, and y. You are finding b.

  20. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    y = mx+b replace knowns to get: (-6) = (8/9)(7)+b multiply out the 7 and 8/8 tp get: -6 = 6 2/9+b That is all the steps so far. Next is subtract 6 2/9 from both sides to get b alone.

  21. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ok, lemme do it and see what I get...

  22. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Would this be the correct step before I do any of the subtractions? -6 - (-6) 2/9

  23. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Not quite. Because it is postive on the one side, you subteact it or add the negative. That has one extra - sign...

  24. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    -6 - (-6) = -6 +6 = 0, which is incorrect.

  25. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    So wait, I'm so confused.

  26. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    It would be -6 + -6?

  27. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Basically, yes. -6 = 6 2/9+b -6 - (6 2/9) = 6 2/9+b - (6 2/9) Which also means: -6 + (-6 2/9) = 6 2/9 - (6 2/9) +b

  28. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    So what do you get when you simplify that?

  29. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Umm.... I don't know haha. This is terrible. I hate fractions!!!!

  30. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    It's getting to the point where I'm about to blow up!!

  31. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    -12? I'm guessing....

  32. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Well, it is a mixed number right now... so it just comes along for the ride. Because they are both negative, you are not going to need about converting both to fractions at the moment. So yes, -12... and the fractin part. -12 2/9

  33. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    So my slope-intercept would be: y=1/8x -12 2/9?

  34. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    THANK YOU JESUS I GOT THIS RIGHT!!!

  35. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yah, that is it.

  36. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Thanks, Eric!! It really does look like I'm in love with fractions. Ughgh.

  37. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    OK, I showed to this point: \(-6=\dfrac{8}{9}\cdot\dfrac{7}{1}+b\) Now, let me show you it all in factions from there. \(-6=\dfrac{56}{9}+b\) \(-6-\dfrac{56}{9}=\dfrac{56}{9}-\dfrac{56}{9}+b\) \(-\dfrac{54}{9}-\dfrac{56}{9}=b\) \(-\dfrac{110}{9}=b\) So you can also write the slope-int as: \(y=\dfrac{8}{9}x-\dfrac{110}{9}\) Which graphs as: https://www.desmos.com/calculator/4y3424y9ye

  38. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Oh!!! Ok. That's better!! Thanks!!

  39. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Not to offend you or anything like that, I was wondering why you started off with -6 = 8/9*7/1 +8...

  40. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    I didn't. It is +b. Not +8.

  41. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Write the equation of the line which has a slope of 8/9 and passes through (7,-6). That means: (x,y) = (7,8) at one point, so x = 7 and y = -6 are valid in one equation. m = 8/9 y=mx+b is the general equation. All I did was substitute what is known: \((-6)=\left(\dfrac{8}{9}\right)(7)+b\) That is how I started. It leaves only b as a variable, which is what I solved for next. =)

  42. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ohhh!!!! Cuz I did it some other way and I got confused.....

  43. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    Yah. Hehe. I can guess with a -1 in your first thing. It is all about looking at what is known and unknown. They want it in y=mx+b form. They gave you 3 of the 4 variables, so you need to find the 4th.

  44. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Hehe. Not nice=) Just Kidding! But anyways.. I see where you're getting that "loved math" from.

  45. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    People tend to shy away from fractions when they are first shoved on them, but they are really not that bad. I think they are just poorly taught. They come in handy, are in all of life, and prep you for dealing with a lot of other math. For example, there are some similar rules for fractions and radicals: To add or subtract, what is under must match. To multiply, just go for it. There are also some differences: To divide a fraction, you flip over the divisor(second one) and multiply. With radicals, they must be the same power to multiply or divide them. So square roots and cube roots won't multiply out the same way as two cube roots or two square roots. So if you know how to work fractions it makes you partially ready for working with radicals (roots.)

  46. e.mccormick
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 1

    And as for real life, a quarter is 1/4 of a dollar, a slice of pie is anywhere from 1/4 of a small one to 1/8th of a large one, yu can order half a sandwitch, the pitch (slope) of a roof in america is given in 12ths, etc.

  47. YanaSidlinskiy
    • one year ago
    Best Response
    You've already chosen the best response.
    Medals 0

    Ohhh!!! Makes total sense. Went into depth with it! Thanks alot!!! I really appreciate it!!

  48. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.