More examples of factoring quadratics with a leading coefficient of 1 | Algebra II | Khan Academy

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  • เผยแพร่เมื่อ 20 ม.ค. 2025

ความคิดเห็น • 517

  • @anthonygrimms312
    @anthonygrimms312 9 ปีที่แล้ว +866

    Amount of times he's saved me for homework is too high

  • @amtheman2000
    @amtheman2000 10 ปีที่แล้ว +339

    wow so much better than my teacher and alot clearer to understand

    • @adhesiveloki1479
      @adhesiveloki1479 10 ปีที่แล้ว +11

      Ikr 8th grade would suck without khan

    • @bijoyeesultana1564
      @bijoyeesultana1564 9 ปีที่แล้ว +1

      +Adhesive Loki WTF im dong this in grade 6 and tomorrows my exam wtf

    • @adhesiveloki1479
      @adhesiveloki1479 9 ปีที่แล้ว +2

      B.S. liar.

    • @adhesiveloki1479
      @adhesiveloki1479 9 ปีที่แล้ว

      B.S. unless you're in an advanced math program. And in retrospect this material is easy

    • @bijoyeesultana1564
      @bijoyeesultana1564 9 ปีที่แล้ว

      Adhesive Loki noo lmao .-. im not lying seriously our studies are advanced here the thing u do there in grade 10 here we do it in 8

  • @sparrowshoot
    @sparrowshoot 10 ปีที่แล้ว +729

    If this guy was my tutor I would be a genius

  • @Ecclestonee
    @Ecclestonee 12 ปีที่แล้ว +57

    Finally! I understand something from math! I have never even thought that this day will come! Thank you Sal!

    • @nowa_rl
      @nowa_rl 3 ปีที่แล้ว +2

      this comment's 8 years old, how are you doing now?

    • @eshnd-1
      @eshnd-1 2 ปีที่แล้ว +5

      @@nowa_rl he’s probably a multi millionaire because of khan academy

    • @jaclyndang4417
      @jaclyndang4417 ปีที่แล้ว

      @@eshnd-1 yuh huh

  • @Bacon56ful
    @Bacon56ful 8 ปีที่แล้ว +245

    That handwriting is distracting me lel, its so nice and sleek

    • @cheyannewolfhard.8546
      @cheyannewolfhard.8546 6 ปีที่แล้ว +5

      IKR! Oml. I thought I was the only one. Lol

    • @anton6812
      @anton6812 5 ปีที่แล้ว +3

      Lmao also he is writing with a mouse

    • @WandenWaffler
      @WandenWaffler 11 หลายเดือนก่อน +1

      HE is definitely not a doctor

  • @twentyfivehourpharmacy6348
    @twentyfivehourpharmacy6348 4 ปีที่แล้ว +124

    Ya’ll are out here saving me in quarantine . This is how I pass

    • @twentyfivehourpharmacy6348
      @twentyfivehourpharmacy6348 4 ปีที่แล้ว +3

      Elijah Elliott obviously it’s boring, I’m stuck at home until May and homeschooled. It’s boring asf but I still have to learn this stuff

    • @electriccommuterbike1349
      @electriccommuterbike1349 4 ปีที่แล้ว

      ..How you holding up?

  • @Keithybox
    @Keithybox 6 ปีที่แล้ว +35

    I love how these vids are more helpful and easier to understand compared to actual lecturers :)

  • @massimoroberts
    @massimoroberts ปีที่แล้ว +13

    I can't even put into words how helpful Khan Academy has been to me, both in school and studying for SAT. I always found factoring to be particularly challenging, and this helped a lot!!

  • @rohancomey1148
    @rohancomey1148 11 ปีที่แล้ว +21

    You just taught me more in one video than my teacher has taught me all year -- it's almost November. Test tomorrow, THANK YOU! This was perfect!

  • @crisptomato9495
    @crisptomato9495 4 ปีที่แล้ว +4

    Because of Corona my math course is cramming three lessons into one class. I just started the unit this Monday and I the unit test is Friday. We go to school every other day. Pray for me. God I’m so happy this is my last year of having to take math.

  • @WarBeardMotoVlogs
    @WarBeardMotoVlogs 5 ปีที่แล้ว +8

    I can't tell you guys how many times I've come here after class to actually learn how to do something. You guys are a lifesaver. Thank you!

  • @Syed_Institute
    @Syed_Institute 8 ปีที่แล้ว +7

    Thank you Khan Academy for helping me through the years. I've start doing my own videos for math now and hope students use your videos and my videos on my channel and other sources to learn.

  • @ajaxtaur
    @ajaxtaur 11 ปีที่แล้ว +6

    Thank you for this. Factoring Quadratic equations has always been an issue for me, and no teacher has ever explained it as you have. I finally understand.

  • @TheMichlFischl
    @TheMichlFischl 5 ปีที่แล้ว +11

    Sal, You are the most amazing teacher in this world!

  • @fum7175
    @fum7175 5 ปีที่แล้ว +174

    Khan academy- when your teachers suck at teaching.

    • @eliehl8769
      @eliehl8769 4 ปีที่แล้ว +2

      Hahah or they just hella lazy

    • @ThuyNguyen-ms5nb
      @ThuyNguyen-ms5nb 3 ปีที่แล้ว

      Lol lmao

    • @rebelpilot7015
      @rebelpilot7015 3 ปีที่แล้ว +1

      Or when you don’t pay attention to online school :/

    • @kenziekins_9289
      @kenziekins_9289 3 ปีที่แล้ว

      LITERALLY ... the amount of times ive had a teacher tell my class, "And if you cant figure out the material or have any questions youtube khan academy" Like. isnt that YOUR job? im confused...

  • @Winter_Blood
    @Winter_Blood 5 ปีที่แล้ว +25

    8:33 When your brain works too fast lol

  • @Kyraaá.2772
    @Kyraaá.2772 4 ปีที่แล้ว +7

    i love when he says "it works!" "that worked!" like we're conquered the world

  • @StanleyTube2000
    @StanleyTube2000 11 ปีที่แล้ว +4

    I'm preparing for MathCounts right now, so all of your math videos are really helpful. Thanks.

  • @Homemadephilosophies
    @Homemadephilosophies 12 ปีที่แล้ว

    I dont think you know how much your videos help me, Im in grade 11 university math and science courses, and its crazy because this is online but you help me more then my teacher! So appreciated! Thank you!

  • @deathstorm3608
    @deathstorm3608 ปีที่แล้ว +1

    Haven't done this kind of math since junior or senior year of high school and im starting back to college for the first time in about 9 years.. My brother tried explaining it and i just couldnt get it..... This helped tons!!! Much appreciated.

  • @erinw8509
    @erinw8509 4 ปีที่แล้ว +49

    who is here self studying

  • @fatimanoorbajwa3865
    @fatimanoorbajwa3865 4 ปีที่แล้ว +1

    This helps almost a decade later. Thanks!

  • @christosbinos8467
    @christosbinos8467 10 ปีที่แล้ว +17

    Thanks bro! much better than my teacher.

  • @akalaskie1466
    @akalaskie1466 3 ปีที่แล้ว

    I took college algebra over 20 years ago and my new college program won't take it. Khan Academy is how you test out of the class so you don't have to retake it. Golden!

  • @Tom-vt7lh
    @Tom-vt7lh 11 ปีที่แล้ว

    This is really helpful, and not only is the information great but you're enthusiasm also rubs off and helps with the memorisation. Most of my teachers are fine, but just don't have your enthusiasm, like they don't actually want to teach us

  • @Physico
    @Physico 3 ปีที่แล้ว +4

    I've never really grasped the concept factoring quadratics, but this video helped me understand! Thank you!

  • @jeskahhjaxx
    @jeskahhjaxx 12 ปีที่แล้ว

    I have never smiled before while learning math - the excitement in your voice while teaching and your methods are just awesome. I'm going to my exam soon and hopefully I'll pass, after watching most of your videos all week I'm sure I will.

  • @2setsofteeth
    @2setsofteeth 14 ปีที่แล้ว +1

    Clear explanations, easy to follow. Excellent how he explains the use of the coefficients: a, b & c in factoring.

  • @AlienAssembly
    @AlienAssembly 12 ปีที่แล้ว

    I just want to thank you. You have helped me, and you are doing a service to the online community by making these videos.

  • @KingPanda-bh4fw
    @KingPanda-bh4fw 5 ปีที่แล้ว +3

    Thanks a lot Khan Academy! You helped me understand concepts that I wouldn't get without videos like these! :D

  • @maziartaghdiry7654
    @maziartaghdiry7654 8 ปีที่แล้ว +10

    fuck school all u need is khan academy

  • @MayaAmolo
    @MayaAmolo 12 ปีที่แล้ว

    I couldn't understand any of this at school but this makes it so much simpler
    You're the best!!

  • @kyungahban1787
    @kyungahban1787 5 ปีที่แล้ว +2

    7th grade from Korea. This was really helpful! What grade do students learn this in U.S.?

    • @acessential3799
      @acessential3799 4 ปีที่แล้ว

      I am also from South Korean but live in US, and I am going into 8th grade, but my mom is making me do this math book during summer break, no grade level written on it, and im learning it so I don’t really know. But based off of the comments, I think it’s 9th grade or mid 8th grade

  • @GregLondon
    @GregLondon 11 ปีที่แล้ว +25

    Thank you, this video explained factoring quadratics what I failed to get out of the 1st 25 pages of my textbook!!!!

    • @bryannguyen658
      @bryannguyen658 11 ปีที่แล้ว +2

      I agree this happened to me

    • @adhesiveloki1479
      @adhesiveloki1479 10 ปีที่แล้ว +1

      Yeah three days of 42 minute lessons explained in less than the first 2 minutes of the video. Get Good

    • @mirandagaunt9564
      @mirandagaunt9564 4 ปีที่แล้ว +1

      Greg do you remember this comment?

  • @juliadi-yan1699
    @juliadi-yan1699 4 ปีที่แล้ว +1

    You make this so easy, I had trouble with this before i watched this

  • @PVTfluffy
    @PVTfluffy 5 ปีที่แล้ว +5

    This guy has saved so much of my time.

  • @adhesiveloki1479
    @adhesiveloki1479 10 ปีที่แล้ว +11

    Khan Academy You da real MVP.

  • @deadlyassian999
    @deadlyassian999 12 ปีที่แล้ว

    YOU ARE THE BEST MATHS AND SCIENCE TEACHER ON TH-cam!!!!!!

  • @cassandrachu5529
    @cassandrachu5529 11 ปีที่แล้ว

    i just learned more in 16 minutes than i have in the ppast 3 days in math class. my teacher is rather inept in teaching THANKS, KHAN

  • @jmiles4life
    @jmiles4life 3 ปีที่แล้ว +1

    This guy is better than my teacher ... thank you so much

  • @elijahjosephm.faustino8823
    @elijahjosephm.faustino8823 4 ปีที่แล้ว

    This explanation you've given me is clearer than some of the other videos I've watched, they took me 3 times to understand, thank you very much

  • @vippen645
    @vippen645 9 ปีที่แล้ว +3

    This video helped me a lot. Thank you very much Khan Academy!!

  • @kazinamimi
    @kazinamimi 5 ปีที่แล้ว +2

    I'm a "connective thinker" which means, when I'm learning something, I'm always noticing or observing things or asking, "I see, but what if you do it like this...?" All of that said to ask: When you come up with the numbers for this type of expression, are there ever any coefficients that WON'T work with the (a+b) and (a•b) parts of the problem? - - I mean, are you just choosing numbers that you know will work for the sake of showing us HOW to SUCCESSFULLY complete the square, or is it possible that there are coefficients that CAN'T be factored, multiplied and added to make the process work?

  • @delavega7408
    @delavega7408 4 ปีที่แล้ว +1

    Love from IRAQ

  • @hashigumbo4486
    @hashigumbo4486 9 ปีที่แล้ว +38

    Teach me senpai

  • @jxbr1376
    @jxbr1376 4 ปีที่แล้ว +1

    thank you! i have now learned more than i learned all this quater, (3 days before exmas)

  • @reenaprabhu2424
    @reenaprabhu2424 5 ปีที่แล้ว +1

    Thanks a lot sir you are the best teacher . You saved me million times

  • @jamjelly7899
    @jamjelly7899 9 ปีที่แล้ว +130

    The sum of 9 and 10 is equal to 21

    • @isaiahgraham4091
      @isaiahgraham4091 9 ปีที่แล้ว +7

      jam jelly Your stupid. 9+10=19.

    • @Leolukpeu
      @Leolukpeu 9 ปีที่แล้ว +17

      isaiah Graham it's a yt joke lol

    • @justindenson7560
      @justindenson7560 9 ปีที่แล้ว +41

      You're the one who said 'your stupid'. Take an English class.

    • @isaiahgraham4091
      @isaiahgraham4091 9 ปีที่แล้ว +5

      Ace Goku No but your fat momma is.

    • @Leolukpeu
      @Leolukpeu 9 ปีที่แล้ว +3

      Ace Goku isaiah Graham yo are you really gonna fight over that shit?That was like six months ago just forget it

  • @cartkart1
    @cartkart1 2 ปีที่แล้ว

    12:20 saving this timestamp for later once i’m done with my notes

  • @laughingsharpie
    @laughingsharpie 12 ปีที่แล้ว

    Thank you so much! My teacher tells us that if we have questions to feel free to ask her after class, then acts like were idiots for not understanding the first time, and really is not help at all :/ And thats when i come home and look it up at khanacademy :D

  • @bradc1103
    @bradc1103 13 ปีที่แล้ว

    This video helped me so much! Thank you! My teacher can't explain how to do this if his life depended on it. Thank you so much! :)

  • @finalscythe
    @finalscythe 14 ปีที่แล้ว

    My test is on in a few hours and you are a legend!

  • @catiecowsill5849
    @catiecowsill5849 3 ปีที่แล้ว

    this guy teaches better then my algebra teacher..hes the reason i have straight a's

  • @GooseTheFlick
    @GooseTheFlick 10 ปีที่แล้ว

    Dude, thanks. I was thinking about EVERYTHING in the equation at once, because I wanted to comprehend the way it worked immediately. But shortcuts seem to make it easier to backtrack.

  • @antoniodurant9365
    @antoniodurant9365 4 ปีที่แล้ว +1

    let do one more Sir is the best

  • @Chris-gk9fk
    @Chris-gk9fk 5 ปีที่แล้ว

    Excellent tutorial. This helped me grasp the concept of quadratics. I was not successful using my university's online learning module! Thank You!

  • @haiperbus
    @haiperbus 9 ปีที่แล้ว +19

    here in Canada we call them trinomials

    • @R0Z3MVRY
      @R0Z3MVRY 6 ปีที่แล้ว +3

      And here in Namibia(south western part of Africa) too. We call them quadratic trinomials

    • @hadaraperez808
      @hadaraperez808 6 ปีที่แล้ว +3

      I call them trinomials and I live in New York

    • @animationspace8550
      @animationspace8550 3 ปีที่แล้ว

      Here in america, we call them trinomials

  • @qiannivan5287
    @qiannivan5287 7 ปีที่แล้ว

    I have an online class, and it is built by more than 100 teacher staffs, and they cant teach as good as you do alone. Thank you.

  • @campbellvice6585
    @campbellvice6585 5 ปีที่แล้ว +4

    I’ve been struggling to learn this for weeks!! This helped me so much

    • @ilyakabanets
      @ilyakabanets 4 ปีที่แล้ว +1

      Me too! It just didn't make sense until Sal explained it! Sal is a savior!

  • @ZachHendrixVoiceOvers
    @ZachHendrixVoiceOvers 9 ปีที่แล้ว +47

    You make learning fun.

  • @TheClone4013
    @TheClone4013 12 ปีที่แล้ว

    Very helpful. Looking through books and it made no sense to me at all but now I have a clear idea :).

  • @Ham.V0
    @Ham.V0 ปีที่แล้ว +4

    im on my way to college for a CS major, Im studying for a placement exam since I did stats instead of precal and this helps a lot since I had forgotten most of my basic algebra knowledge

  • @zxphiz
    @zxphiz 5 ปีที่แล้ว

    I'm really grateful for Khan Academy

  • @taobeans6178
    @taobeans6178 11 ปีที่แล้ว

    omg, i'm crying right now. i just aced my math test because of this video; now my mom won't take away my car keys. thank you khan, i owe you my life. seriously.

  • @_claymore6705
    @_claymore6705 4 ปีที่แล้ว +1

    can u do how to facotrisation using algebric identies

  • @SJMgames7
    @SJMgames7 6 ปีที่แล้ว

    I hope your channel becomes more bigger and the best

  • @scottwilliams8479
    @scottwilliams8479 8 ปีที่แล้ว +1

    Very helpful lesson. Thanks a lot!
    Maths can be so easy with a good teacher! :)

  • @BMurdaDaSteppa
    @BMurdaDaSteppa 11 ปีที่แล้ว

    That doesn't matter, if someone is telling you to factor it, you either assume it's equal to zero of if it's in the form
    Ax^2+bx+c=D you subtract D from both sides and then factor.

  • @Rewruio
    @Rewruio 11 ปีที่แล้ว

    @Jacob Fox then split the middle Term to make it as 2x+9x and then factorise x^2+2x+9x+9 into x(x+2)+9(x+1)

  • @HarrypotterHP7
    @HarrypotterHP7 13 ปีที่แล้ว

    Khan you've done it again, Great job!

  • @kit3351
    @kit3351 3 ปีที่แล้ว

    why do we just let random ppl teach us like no wonder i’m so bad at math. this guy explained it clearer than ANY of my other teachers jesus christ

  • @frankyu9725
    @frankyu9725 9 ปีที่แล้ว +10

    Thanks man, I've stuck for a year. Finally

    • @saketnaik1
      @saketnaik1 6 ปีที่แล้ว

      oh yeah yeah , finally

  • @natashanewton1444
    @natashanewton1444 2 ปีที่แล้ว

    Thank you, thank you! You made an intimidating concept make so much sense! I truly appreciate you!

  • @honeybear9
    @honeybear9 4 ปีที่แล้ว +1

    You're a hero

  • @Peter_1986
    @Peter_1986 11 ปีที่แล้ว

    You can more easily figure out the x intercepts for graphs if you factor an expression, because if you set (x+a)(x+b) = 0 then you immediately know that x must be either -a or -b.

  • @johnnyd7017
    @johnnyd7017 4 ปีที่แล้ว +1

    Thanks

  • @Kwanghya
    @Kwanghya 3 ปีที่แล้ว +1

    a lifesaver, a freaking LIFESAVER!!!!

  • @MiaLopezdevos
    @MiaLopezdevos 13 ปีที่แล้ว

    I love your handwriting. Tell me: are you using a tablet pen? What software are you using and how are you recording your screen?

  • @lvyvl4836
    @lvyvl4836 9 ปีที่แล้ว +36

    What if the value of x is more than 1?

    • @DS-uo1zy
      @DS-uo1zy 9 ปีที่แล้ว

      still works

    • @SuperKx85dude
      @SuperKx85dude 9 ปีที่แล้ว +27

      +Li Yi well then you are fucked.

    • @latoriacalloway1526
      @latoriacalloway1526 8 ปีที่แล้ว

      That's What I'm Saying...

    • @ohEastie
      @ohEastie 7 ปีที่แล้ว +1

      I dont care if this is a year later, you can use the quadratic formula or something I've learned in class called "The Trick" where you multiply a*c and whatever you get you have to find factors of the product that equal to b, you then put both factors over "a", simplify them, the denominator is the coefficient and the numerator is the constant

    • @sirgrinder
      @sirgrinder 7 ปีที่แล้ว

      inside and outside bridges

  • @markussommarberg703
    @markussommarberg703 7 ปีที่แล้ว

    Thanks Sal, you just saved me from my homework!

  • @Libra_Man_Nell
    @Libra_Man_Nell 11 ปีที่แล้ว

    This helped me on my homework... thank you soooo much. Now I know what to do now. :D

  • @errolangbaka9173
    @errolangbaka9173 11 ปีที่แล้ว

    Thank you so much! You are much better than my IB teachers! :D

  • @satorlu
    @satorlu 10 ปีที่แล้ว +2

    Great explanation, thanks.

  • @anishjoshi3669
    @anishjoshi3669 3 ปีที่แล้ว

    I love all your video they are really Helpful and the Teaching is Amazing

  • @CptMisadventure
    @CptMisadventure 3 ปีที่แล้ว +1

    @Khan Academy how would I go about factoring 16x^2-18x-9

  • @snynn
    @snynn 3 ปีที่แล้ว

    The biggest hero for any high school student

  • @puja877
    @puja877 12 ปีที่แล้ว

    Best math teacher!!!!!!!!!!!!!

  • @robertvenable3354
    @robertvenable3354 5 ปีที่แล้ว +1

    Excellent video. Keep up the great work.

  • @Imbobbyd
    @Imbobbyd 3 ปีที่แล้ว +1

    thank you for this VERY helpful video!!

  • @audreyylyn
    @audreyylyn 8 ปีที่แล้ว +5

    saving my pre-calc grade :))))))

  • @BahClipss
    @BahClipss 3 ปีที่แล้ว +1

    Thanks so much my guy 👍

  • @davidgrasov8587
    @davidgrasov8587 8 ปีที่แล้ว

    Thats what i think.
    I found my place to study :D
    Great channel

  • @LasagnaMAX
    @LasagnaMAX ปีที่แล้ว

    Crazy how some dude on the internet can do it better that an in person lesson.

  • @nousername12127
    @nousername12127 6 ปีที่แล้ว +44

    I was procrastinating and and my test is tomorrow and kind of panacking

    • @FroggieIsHere
      @FroggieIsHere 6 ปีที่แล้ว +2

      Sophia RederTM IM IN THAT SITUATION RIGHT NOW

    • @anna-kk4zl
      @anna-kk4zl 6 ปีที่แล้ว

      metoO

    • @Cobalt985
      @Cobalt985 5 ปีที่แล้ว +1

      Same here haha

    • @jamescampbell8307
      @jamescampbell8307 5 ปีที่แล้ว +1

      Dealing with the same thing

    • @chickenpox5434
      @chickenpox5434 5 ปีที่แล้ว +2

      And now after sleeping through algebra here I am

  • @mortenhgseth6351
    @mortenhgseth6351 12 ปีที่แล้ว

    Sir, you are a great teacher =)

  • @balla4life22324
    @balla4life22324 10 ปีที่แล้ว

    Yo this helped so much thank you khan academy!!!!!

  • @deepanshusuman9921
    @deepanshusuman9921 5 ปีที่แล้ว

    Sir please give some sample problems also so that we can do practice and there answer also

  • @mevorathfjorathk.6219
    @mevorathfjorathk.6219 8 ปีที่แล้ว

    great video. your this channel is how I study. if full on is no acceptations so far

  • @LearnMathsFree
    @LearnMathsFree 9 ปีที่แล้ว +1

    Thank you for your video.

    • @amjadmirza2343
      @amjadmirza2343 8 ปีที่แล้ว

      +Learn Maths Free u gonna dwnlload nd upload it ?? u cm fr tht nd thknin

  • @evonyg3203
    @evonyg3203 11 ปีที่แล้ว +15

    what if it's like
    2x^2-8=0 ?
    Is there an understood 1x? as the bx term? I:

    • @cheyanneguillory5149
      @cheyanneguillory5149 11 ปีที่แล้ว +2

      thats what I'm looking for

    • @ksi3822
      @ksi3822 6 ปีที่แล้ว +1

      x=3

    • @drowsy5384
      @drowsy5384 6 ปีที่แล้ว +3

      2x²-8=0
      2x²=8
      x²=4
      x=✓4=±2

    • @acessential3799
      @acessential3799 4 ปีที่แล้ว

      That’s a Simple Quadratic Equation so it would be
      2x^2-8=0
      2x^2=8
      x^2=4
      x=square root of 4
      x=+-2
      I’m going into 8th grade btw 🤷🏻