How to Find the Vertex of a Parabola (NancyPi)

Поділитися
Вставка
  • Опубліковано 14 тра 2018
  • MIT grad explains how to find the vertex of a parabola. You can get the vertex from the parabola equation (standard form or vertex form). To skip ahead: 1) For how to find the X-COORDINATE of the vertex point from a STANDARD FORM equation of a parabola (like y = -2x^2 + 4x + 1), skip to time 0:16. 2) For how to find the Y-COORDINATE of the vertex, skip to time 1:34. 3) For how to get the vertex point from VERTEX FORM instead [like y = 2(x - 1)^2 + 3], skip to 2:24. 4) For what to do if the signs are confusing (ex. if the equation has X PLUS A NUMBER instead of x minus, like in y = 2(x + 3)^2 + 4), skip to 3:34. Nancy formerly of MathBFF explains the steps.
    For my video on COMPLETING THE SQUARE for a quadratic polynomial, jump to: • How to Solve By Comple...
    Follow Nancy on Instagram: / nancypi
    Twitter: / nancypi
    HOW TO FIND VERTEX:
    How you find the vertex depends on whether the equation you're given is in "standard form" or "vertex form". How do you know if your problem is vertex or standard form? Each one has a very different form.
    What is standard form? The STANDARD FORM equation is a quadratic polynomial and looks like y = ax^2 + bx + c without any parentheses (it has not been changed into another form by completing the square). If your equation looks like this, your vertex will be a point with an x-coordinate that is -b/(2a) where you can find a and b by comparing the standard form parabola formula to the equation you were given. Then, you can get the vertex y-coordinate by taking your original equation and plugging in the x-coordinate you found and simplifying until you've solved for y.
    The VERTEX FORM is also a quadratic equation but is in the form y = a(x - h)^2 + k. It's easier and faster to find the vertex from the parabola vertex form, because the vertex is just the point (h,k) and h and k are values you can pull straight from the equation by matching the equation you were given with the vertex form formula that uses h and k. If your given quadratic equation has x plus a number, in parentheses, instead of minus a number, like y = 2(x + 3)^2, then you can rewrite the equation as subtraction of a number, like y = 2(x - (-3))^2, since adding 3 is the same as subtracting negative 3. This means that your h value will be negative 3.
    Note: if you want to be able to convert your standard form into vertex form with a perfect square in your equation, you will need to "complete the square" first to get your parabola equation into vertex form.
    On the graph of a quadratic function or parabola, the vertex is either the lowest point on the parabola (the minimum) if the parabola is opening up, or it is the highest point on the parabola (the maximum) if the parabola is opening down.
    For more of my Algebra, Algebra 2, College Algebra, and Geometry math videos on quadratic functions and help with other mathematics topics, check out: nancypi.com

КОМЕНТАРІ • 311

  • @shmrnt5996
    @shmrnt5996 4 роки тому +321

    Is she writing backwards? Because how can we see it perfectly but she is writing on the other side of glass?

    • @trinitykayla1204
      @trinitykayla1204 4 роки тому +26

      Shmrnt • pretty sure she’s looking at a mirror

    • @rajeshwaryadav6260
      @rajeshwaryadav6260 4 роки тому +44

      camera automatically flips it try at home

    • @lasernikixcex
      @lasernikixcex 3 роки тому +48

      She probably wrote it normally and then flipped the video while editing

    • @PowshuArt
      @PowshuArt 3 роки тому +8

      Rajeshwar Yadav if you flip it at home the voice flip it too

    • @adrianrafael6538
      @adrianrafael6538 3 роки тому +28

      you guys complicate things too much. she writing backwards

  • @novellaclaiborn9435
    @novellaclaiborn9435 4 роки тому +28

    math test tomorrow and you put it in a very simple understandable version, others seem to do too much and i get lost in there reasoning. straight to the point

  • @Pasperdu
    @Pasperdu 6 років тому +91

    You helped me pass my first Calculus class! Glad to see you back in action! 💻🤓📖📚

    • @itslongford
      @itslongford 2 роки тому

      this is algebra 1

    • @Pasperdu
      @Pasperdu 2 роки тому +8

      ​@@itslongford Algebra is used in basic calculus and beyond; it's a necessary learning component. Good luck.

    • @tjdtns1984
      @tjdtns1984 2 роки тому

      @@Pasperdu Learning calc but needs to check alg 1 basic? Good luck bro

    • @Pasperdu
      @Pasperdu 2 роки тому +8

      @@tjdtns1984 Not everyone's story is the same. Wasn't lucky enough to learn as a child and had to catch up. Graduated University and am gainfully employed now though, thanks.

    • @yaboyskates5126
      @yaboyskates5126 2 роки тому

      Bruh why my algebra 1 teacher teaching me this then???

  • @planomathandscience
    @planomathandscience 6 років тому +6

    Forget her complete and easy way of explaining, she writes backwards, so nicely. My hero.

    • @TheAirZeus
      @TheAirZeus 5 років тому +5

      She writes forward and reverse/mirrors the video in the editing process. It appears she's left-handed, when she's actually right-handed.

  • @angahlstrom14
    @angahlstrom14 3 роки тому +17

    That was SUPER helpful. She explained each steps (right when I thought she'd skip it like everyone else), and the rationale behind it all. Putting it into greater visual context would have helped me understand the more important "why" + "how this works on a graph" though. Thanks :)

  • @szejer4184
    @szejer4184 6 років тому +12

    You helped me pass trig and calc 1-2
    Glad to see you back doing what your passionate about. And helping others

  • @melissacheckland8243
    @melissacheckland8243 3 роки тому +7

    Thanks so much! You have such a calming way of explaining what otherwise seem like complex math problems.

  • @LuizMartins1989
    @LuizMartins1989 4 роки тому +2

    I spent hours trying to find a video that makes math easier than it looks and she does just that! She is amazing! I literally watched 20 seconds of this video and found what I needed!

  • @PixuRz
    @PixuRz 6 років тому +221

    I’m done with math for college but just wanted to watch this vid cuz she makes math seem so easy lolol

  • @DSingh25
    @DSingh25 6 років тому +7

    You helped me a lot in my Calculus classes. So happy I am done with all my math classes.

  • @TheNaimi
    @TheNaimi 4 роки тому +7

    Thank you Nancy
    You've made my life so much easier throughout the years

  • @danicerul4565
    @danicerul4565 6 років тому +1

    Thank you forcoming back, I miss you! You are awesome!

  • @Albertobelmonte9
    @Albertobelmonte9 6 років тому +16

    The cool thing is -b/2a is derived from the quadratic formula. Also you can get the discrimanant from + or - square root b^2-4ac.

  • @lynnbryant4477
    @lynnbryant4477 5 років тому +4

    Watched several videos (some within my online text) and I still didn't get it until I watched this video. Thanks, gal!

  • @UZAIRKHAN-pb5dl
    @UZAIRKHAN-pb5dl 6 років тому +92

    We miss u.

  • @lishalopez5252
    @lishalopez5252 5 років тому +4

    Thank you so much, my teacher has been explaining this for 2 days and no one understands it, including myself. I understood you in five minutes. Can’t wait to share this video with my friends!

    • @dheerajtiwari7534
      @dheerajtiwari7534 4 роки тому +1

      Lisha López maths is easy when teacher is good. 😀

  • @alexhemingway2220
    @alexhemingway2220 3 роки тому +1

    Thank you so much!! Your videos are always super straightforward and helpful

  • @cynthiagonzalez8702
    @cynthiagonzalez8702 6 років тому +17

    We have missed you Nancy!! 😀

  • @akhileshkumbhar6160
    @akhileshkumbhar6160 6 років тому +2

    Thank you very much!! U r the best Math teacher I have ever come across!! Love u!!

  • @mikehawk2885
    @mikehawk2885 6 років тому +7

    Thank you for the new video! Although I am way past pre-calculus/calculus required fo me, mostly thanks to your excellent intuitive explanations, this video was a fantastic to renew my understanding of a concept(even though its not currently needed).
    Will there be a structure to your videos uploads? Such as algebra, geometry, calculus, etc? Any plans on doing Linear Algebra videos by chance?

  • @IvanMTG1
    @IvanMTG1 6 років тому +34

    It's almost 12:30 AM in CA, but I don't care; Ima watch this!

    • @Albertobelmonte9
      @Albertobelmonte9 6 років тому +3

      IvanMTG1 wow we live in the same time zone awesome

  • @nmontaquila
    @nmontaquila 3 роки тому +1

    This video was super helpful. thanks! and keep up the awesome work!

  • @IICOR1552
    @IICOR1552 2 роки тому +1

    I received more useful information in the first 2 minutes of your video than the 300 videos I watch!!! Thank you!!!

  • @TJ-jx6dx
    @TJ-jx6dx 3 роки тому +1

    I really wish I found you at the beginning of the year... I'm actually shedding a tear over here.

  • @robertdiaz809
    @robertdiaz809 4 роки тому +10

    Your explanations and the handwritten notes are incredibly helpful. I do share Agasthya's question below, the one referencing the need for a negative in front of the 3 (in the value of h, as you explain at 04:15). Karlie and Napalm had discussed it a year ago and it seems a contrast to your explanation at 02:50, whereat you express the vertex as h-(-1), and that gives us the value of 1, but the 1 there was negative. I do see in Desmos that your answer is indeed (1,3) but I'm left wondering if that could be the result of squaring 2 numbers). Could you please clarify that so that I may use your guidance in our tutoring session. Thanks so much.

  • @jlunde35
    @jlunde35 6 років тому +1

    Great seeing you again Nancy.

  • @prashantabrol4501
    @prashantabrol4501 4 роки тому +1

    You made it look so easy, thank you so much 💞

  • @parmindersinghraj7424
    @parmindersinghraj7424 5 років тому +1

    Awesome video and many thanks for your efforts!

  • @vintagequill2168
    @vintagequill2168 3 роки тому +2

    I was just thrown into 9th grade math whilst in 8th grade right in the middle of the year. This was so helpful, thank you thank you thank you!

  • @pauldeacon7099
    @pauldeacon7099 4 роки тому +1

    A very helpful video, I was stuck in my homework, now I can finish the final few questions of the chapter.

  • @dammarathdarkmusic4237
    @dammarathdarkmusic4237 6 років тому +1

    Wooooooooo. You came back. Very impressive amiga.

  • @docomocco1396
    @docomocco1396 Рік тому +1

    you explained it soo well !!! thanks a lot.

  • @georgevladimirovich7190
    @georgevladimirovich7190 5 років тому +1

    Excellent Job Nancy. My daughter is doing academic math and this helps her a lot.

  • @rosepulaski3542
    @rosepulaski3542 6 років тому +1

    Thanks so much for the video, suddenly everything makes sense!

  • @donaldg1382
    @donaldg1382 5 років тому +1

    This video helped me much ! Thank you !

  • @professorshifu618
    @professorshifu618 Рік тому +1

    That was an awesome lecture. Thank you.

  • @mariano2078
    @mariano2078 5 років тому +1

    I love you Nancy. You're A Great Inspiration

  • @Rayram555
    @Rayram555 4 роки тому +1

    Where have you been? Looking to see more . Thank you . Great videos!

  • @nuevosarahjoyt.8525
    @nuevosarahjoyt.8525 3 роки тому +1

    Aw, thankyou so much it's been a year when u upload this video and it's very helpful uwu

  • @Lila-dk3yl
    @Lila-dk3yl 3 роки тому +1

    Helped a lot! Thanks!

  • @zacharyschoen1877
    @zacharyschoen1877 3 роки тому +1

    Keep crushing it #NancyPi !!! I use your videos whenever I get stuck on my math problems in 1,001 practice problems Algebra 2 for Dummies.

  • @nazombie7935
    @nazombie7935 4 роки тому +1

    Hey this was a great lesson!! On finding the vertex form I can never remember on a test when the eqation has a positive sign that the number is negative!! thank for this video!! You explain it better than a college algebra book and your very pretty

  • @hanf4415
    @hanf4415 5 років тому +1

    oh thanks for explaining the last part. I've been going crazy trying to understand the signs for the vertex form and thats why my answers were wrong because I wasn't evaluating the negative sing..

  • @ellehermosura2181
    @ellehermosura2181 3 роки тому +1

    Thank you so much! This is the only video I understood(in math)

  • @arifaameer1393
    @arifaameer1393 2 роки тому +2

    That was very Informative

  • @div6002
    @div6002 3 роки тому +2

    POV: You have a math assignment about finding the vertex or a parabola and you didn't have a clue what your teacher taught you

  • @aquienpuedaimportar3028
    @aquienpuedaimportar3028 6 років тому +1

    Thanks very much for helping us.

  • @karlieramirez5991
    @karlieramirez5991 5 років тому +17

    i have a question, so with the vertex form why wouldn’t you bring the negative sign over?

    • @syware1
      @syware1 5 років тому +8

      Karlie Ramirez
      She explains this at 4:00. Basically a(x-h)^2+k is the standard form we want to view it in. When (x - h) is (x + h) that means “h” must be negative because (x - (-h)). Those negatives cancel each other out to become positive.

  • @DANIELDALLAS_MATHs
    @DANIELDALLAS_MATHs 4 роки тому

    Nancy, nice! Keep doing your job!

  • @lucascorea3215
    @lucascorea3215 5 років тому +1

    THANK YOU THIS SIMPLFIED IT SO MUCH THANK YOU 🙏

  • @shushannataylor7324
    @shushannataylor7324 5 років тому +1

    Thank you so much I appreciate your explanation

  • @johnryder1713
    @johnryder1713 5 років тому +1

    Thanks for the end on the signs Nancy, really easy to miss if you didn't

  • @supamanvag
    @supamanvag 6 років тому +2

    She's back!

  • @unique6228
    @unique6228 4 роки тому +1

    thank u so much u are an amazing person easy simple short , i respect how good y can teache math

  • @samgloman6754
    @samgloman6754 4 роки тому +1

    Thank you so much doing a test right now.

  • @LiOnHeLl-kc8vy
    @LiOnHeLl-kc8vy 6 років тому +1

    This help me a lot for studying my SAT on parabola. Wish me luck on the SAT.

  • @anushka0412
    @anushka0412 2 роки тому +1

    Oh I got it real quick now
    Thank you!

  • @ravenliani
    @ravenliani 5 років тому +1

    Very helpful , Thank you so much !!!!!

  • @muazkashif8554
    @muazkashif8554 6 років тому +15

    YES. FINALLY.

  • @yosexx162
    @yosexx162 3 роки тому +1

    wow that is impressive XD and a really good way not to get bored out of explaining basic stuff that you already know jjeeje XD nice technique !! =)

  • @javierarguelles6629
    @javierarguelles6629 6 років тому +4

    I love your videos! Love from Mexico 🇲🇽

  • @ink8660
    @ink8660 5 місяців тому

    so simple and nice, thank you

  • @rhondacreel7103
    @rhondacreel7103 2 роки тому

    Thank you. Helped so much!

  • @7949RAJ
    @7949RAJ 6 років тому +1

    Thank u nancy, u r the best

  • @sirdrew6233
    @sirdrew6233 3 роки тому

    It took me a month before actually understanding about finding the h, because the negative sign ...this video is perfect thank you!

  • @mohitsinghania5155
    @mohitsinghania5155 Рік тому +2

    Thank you so much and love you ❤️.

  • @charliemorris4954
    @charliemorris4954 4 роки тому +1

    you literality just saved my damn dumb life, NancyPi. Thank God you were made.

  • @MrVoayer
    @MrVoayer 6 років тому

    Welcome back, dear Nancy ! I want to date you regularly ! On your UA-cam channel !!!

  • @TribeOfTestosterone
    @TribeOfTestosterone 2 роки тому

    Thank you very much for your help, its amazing the way you explain math i love it 💗🌹

  • @baileyd196
    @baileyd196 3 роки тому +1

    THANK YOU SO MUCH ❤️

  • @Max47340
    @Max47340 2 роки тому

    Nancy you are one hot math teacher! Thank you for making it so simple and easy!

  • @zaylee461
    @zaylee461 2 роки тому

    you are a blessing i swear 💗💗💗💗

  • @abunchofsmallaliens7250
    @abunchofsmallaliens7250 4 роки тому +1

    Thank you so much!

  • @tsegayghidey5454
    @tsegayghidey5454 5 років тому

    thank you , you really help me

  • @sdmartens22
    @sdmartens22 6 років тому +4

    The -b/2a expression is seen in the quadratic formula. Geometrically the x-coordinate of the vertex should be midway between the two zeros of the parabola (when they exist); the quadratic equation states this algebraically.

    • @ronaldjensen2948
      @ronaldjensen2948 6 років тому

      The vertex of a parabola happens when the first derivative is equal to zero.
      y=ax^2+bx+c -> dy/dx = 2ax + b
      set dy/dx equal to zero:
      0 = 2ax + b
      solve for x: x = -b/(2a

  • @hassanhadi3892
    @hassanhadi3892 4 роки тому +1

    you are the best ...thank you very much

  • @rckyloopy5621
    @rckyloopy5621 3 роки тому +1

    Thank you so much,wish you were my math teacher.

  • @shrudayie
    @shrudayie Рік тому

    your voice is so calming and easy to listen to thank u sm ur also very pretty

  • @jimintrash552
    @jimintrash552 4 роки тому +1

    thanks for saving my life ily

  • @chinmayibharadwaj4294
    @chinmayibharadwaj4294 11 місяців тому

    Thank you so much!!☺️

  • @RealCoachingCo
    @RealCoachingCo 3 роки тому +1

    Thank you!

  • @Esbheidhy
    @Esbheidhy 4 роки тому +1

    I love you thank you soooo muchhhh

  • @ss3mania28
    @ss3mania28 6 років тому +1

    She’s backkk

  • @American_Made
    @American_Made Рік тому

    My favorite vdeo of yours.

  • @chiozo11
    @chiozo11 4 роки тому +1

    Thank you much

  • @shawnd.8498
    @shawnd.8498 2 роки тому

    Wow! You made finding the vertex stress free. Our math teacher gets irked that we can’t learn fast enough.

  • @alexcardoso657
    @alexcardoso657 3 роки тому +1

    How are you writing like that? This is awesome! You have earned yourself an extra subscriber!

  • @j0hmama
    @j0hmama 6 років тому +2

    Do a video on Correlation analysis

  • @Skiba_Vlogs
    @Skiba_Vlogs 2 роки тому +1

    This is gonna help me pass my finals🙏🏻

  • @adamhodges2539
    @adamhodges2539 2 роки тому +1

    Okay... What I want to know now is, are you writing backwards on a piece of glass? How long did it take you to develop this skill? Or, is this some kind of technology that I'm unaware of?

  • @undercoverperson5877
    @undercoverperson5877 4 роки тому +2

    I watched Brian Mclogans video on this and by god did he make it 100 times harder than it needed to be

  • @spaceship_from_saturn7372
    @spaceship_from_saturn7372 3 роки тому +2

    Nacy be saving my grade in math 😩✋

  • @johannesramos6317
    @johannesramos6317 4 роки тому +1

    Thank you! I answer several questions correctly

  • @emilyvaldez6810
    @emilyvaldez6810 6 років тому +1

    How do you know if the problem is either a vertex or standard form?

  • @justinmeyer8046
    @justinmeyer8046 4 роки тому +1

    Looking forward to discrete math module when 2nd semester starts 24 August. Enjoy her lessons.

  • @AlbertDavidABorja
    @AlbertDavidABorja 2 роки тому

    Thank for this

  • @SurajChauhan77777
    @SurajChauhan77777 5 років тому +1

    Will you please do a video on Probability ?

  • @IICOR1552
    @IICOR1552 2 роки тому

    WOW!! great video

  • @TheBinary0101
    @TheBinary0101 6 років тому +1

    Thx Nancy ..!!

  • @Albertobelmonte9
    @Albertobelmonte9 6 років тому +2

    Nice keep it up.