Algebra: Formulas From Geometry

[meprettylilthing]

Excellent video!!!!

[Yumi78227]

thank you

[videomathtutor]

@Yumi78227 You're welcome.

[MrDrumDrumz]

Wow, I learned in 23 minutes what my teacher couldn't teach me in two months ha! thank you for making these videos they have certainly helped me improve a lot in my math thanks!

[tracylovesuju]

this video really helps me to catch up each lesson that my Geometry teacher teach us!!!!.........

VERY USEFUL!!!!!!!!!!!!!!!!

[Debedeb]

I wish on this video you would show simple examples to find each formula such as A, P, ETC I really enjoy learning with your videos. You have done a wonderful job. those who are giving negative response, notice this video is ; a " formula" video only !!!! It is super helpful to learning all the formulas you need to know for Geometry ;D Perfect

[videomathtutor]

@Debedeb I will do that when I cover this topic in a future geometry lesson. I also will when I do my "test Prep" videos for SAT and ACT.

[Debedeb]

@videomathtutor Thank you ;D so much for your help. YOu made a huge difference in my and others life from sharing such great one on one based lessons. Don't change a thing. Mothers going Education ;D is my slogo lol but being on topic, I am mother of 3 kids 2 in college, and I am trying to walk the step I preach. My teachers in the school I attend do nothing much less a great lesson as you have shared for free for us. Thank you. Let us know on the new videos. Beautiful ppl make for a better pla

[videomathtutor]

@Debedeb Glad to know I can help! Be aware not all lessons are free. I need funds to get better A/V equipment so I can create better videos. Please tell others about my work, and encourage them to get my DVDs too! Keep Studying!

[Debedeb]

@videomathtutor I will do that and thank God atm these are working for me. I will push your instructions with the office of tutor helpers for math students. I will also keep posting with my friends for thier children who may struggle with math. I wish you luck with your advancements and again I want to say thanks. I could not have gotten as far as I have without some ppl like you! MIght want to maybe feature your Dvd's before each video starts. I didn't realize you had them. ;D good luck!

[Debedeb]

@videomathtutor I will try my best to share more of your videos in school and out. If they help me then they are most likely helpful to others. Might I suggest putting your Dvd's at the beginning of your lesson videos as well. I had no clue you offered this.;) Sorry I don't know how to check these comments and lucked into seeing these. I am using my formulas ATm I learned off ur video ;) putting to the test and things seem to be well. I really liked that video.

[minicheesedingdong]

pretty good!! This'll definitely help me on THE TEST. Thanks!!!

[Debedeb]

ty for sharing

[SolidSnake3131]

Hey, thanks. Your videos are great, really helpful. You are better than my teacher for sure.

[MsShellyrose]

this is will help me take the test . Thank you

[videomathtutor]

@MsShellyrose Glad to know! Good Luck, and Keep Studying!

[sengdao2622]

@videomathtutor Good! This will help me on my test on 6/4/11! It's hard!

[bachgod]

well done!

[bettmm]

TY..math teacher for all VIDEO'S. I'm able to comprehend problem

math area's since I discovered YOU.

[01JH]

Great review. Thanks! Loved the graphics and the manipulatives. I'd like to understand how they derive the formulas for the spheres though. Where do they get the 4 and the 4/3rds? Also, what program did you use for create your graphics.  Again, great job on visuals.

[videomathtutor]

@01JH The formula is most easily derived using calculus. I used a VERY old Mac OS 9 program to make the graphics.

[bachgod]

@videomathtutor Very good job Mr.Luis. You are amazing. On one of your videos comments you sayd: I am not a teacher I am a tutor, well Luis you are a Natural or born teacher those qualities are only for people like you who are by nature excellents teacher, not because the teachers have degrees or PhD. You are creative, passionate,fune, and smart with the math, qualities than 99 % of the teacher do not have, (KEEP)+(GOING)= god bless you.

[videomathtutor]

@bachgod Thanks for the kind words! I will keep going!

[nieceypiecey100]

Great great video. thanks for explaining!

[ravikanthroyss]

oh fantastic lecture by the teacher. i want to thank to you tube governing body. in my class no one taught me like this . diagramatic representation is we can not forget.

[Griffinsdad3401]

The cube is a Platonic Solid.

[JiaJunzou]

thanks alot

[sapy52]

i hate geometry

[antilive68100]

thank you for the help

[DBSstudios]

thank you for the help

[videomathtutor]

@DBSstudios You are welcome!

[simplyadorkablex3]

found this very helpful, thanks!

[scheherazade818]

This is awesome and helpfull - thanks a lot !!!

[arqlizcarter]

Thank you so much for you videos they are so great!! :-)

[dineshsk9]

Hi.. I cant watch ur 1 video " Algebra : Introduction to Algebra - Full Lesson " m in australia ..whenever I try to watch this video it says This rental is currently unavailable in ur country ..what is that ..? I didnt get that plz let me know what should I do to watch this video ..

[videomathtutor]

@dineshsk9 The lesson is only available to rent in the USA (apparently). If you wish to watch, you will probably need to buy the Video On Demand or the DVD at my videomathtutor website.

[tierramor]

A mi me gustó este video. Especialmente que ya tiene las formulas escritas y no hay que esperar para que los escribe como se ve en otros videos.

[curtthekrab]

thisis so funny

[XxxMysticalxRosexxX]

omg i'm such a nerd! I'm only 15 years old, and I'm taking Calculus xD

i'm super good at math, but this could have been helpful if I watched this 2 years ago when i was in geometry oh well....

i love learning math so much!! It's like a puzzle, I want to put all the pieces together so I can solve the puzzle (in this case the math problem/equation)

I'm such a nerd but I love to enrich my learning as much as possible so i can get into a highly selective college xD

[LGAGAFAN21]

thank u!

[ballsequer]

so boring

[videomathtutor]

@ballsequer Yeah, this video kind of is a bit boring (but is informative!). It just lists formulas. Sorry I could not make more exciting. I don't have a budget to include exploding cars or hot bikini babes in my videos.

[rick6011]

@videomathtutor lol this video is really infroming

[joannesiano]

hey good vid but i dont get at 6:14 i dont get why d=s square root of 2 can you explaint o me why

[videomathtutor]

@joannesiano I can, and will in a future video. You can do it yourself using Pythagorean Theorem.

[Widdakay]

cool, i cant hear it.

[videomathtutor]

@Widdakay VIdeo is in mono, not stereo. Adjust your audio. Sorry for this. New videos will be in stereo.

[Widdakay]

@videomathtutor thank you!

[mixolidianmode]

wheres the part 2 lol

[videomathtutor]

@mixolidianmode There is no part 2.

[mixolidianmode]

@videomathtutor =-[

[thatbrooklynchick13]

thanks now I can definitely pass my test monday morning

[videomathtutor]

@thatbrooklynchick13 Glad I could help!

[dutchtarantino]

My first comment lacked a "b" at the end, as you need to approve the comments, please be so kind to approve the my second comment, including that "b".

So the correct formula for the figure at 09:28:

(h1 x b) + 1/2(h2 - h1)b

[videomathtutor]

@dutchtarantino Actually, we are BOTH correct (assuming the corrected formula with the added b). You can algebraically manipulate your formula to get mine. Give it a try.

Not sure why you thought my formula was "clearly" false, when all I did was place the trapezoid on its side, and swapped the variables (which would make it the "same" formula).

[dutchtarantino]

The formula for the trapozoid provided at 08:55 is correct:

A= 1/2(b1+b2)h

Sadly the formula for the next figure provided (09:21) is false, as it is the exact same formula you provided for the previous figure, and the figures obviously don't match in relation. The only thing you do in the second formula is switch height (h) and base (b), and this is clearly false

A=1/2(h1+h2)b

Here we need the area (b x h1) PLUS the area 1/2(h2 - h1)

Thus (h1xb)+1/2(h2-h1)b

[michalchik]

@dutchtarantino H1xB+ 1/2(H2-H1)B = H1xB + 1/2xH2xB - 1/2xH1xB = (H1xB- 1/2xH1xB) + 1/2xH2xB = 1/2xH1xB + 1/2xH2xB = 1/2(H1+H2)B

The formula you gave is correct, but it equals the formula they gave and theirs is slightly simpler.

[free2waait]

you are awesome.

[videomathtutor]

@free2waait Thanks! I'm happy to have helped you!

[EricCris10sen]

I am in the military right now, and I was planning to take courses of math and other subjects, but I am really just wanting to get math done. I forget which one is more advanced than the other, algebra or geometry, but Im sure geometry is. And that is the class I took last in high school. I have been in the military for 3 years, so that means 3 years of no math. I know it is going to be EXTREMELY difficult to go back to it. Any suggestions?

[videomathtutor]

@EricCris10sen Start with the "Basic Math" videos I made. They are free, and are designed for those from 7th grade through college. Then slowly move up to the Algebra videos.

[king7wood]

Out of chaos, Euclid arose

[nuuunudux]

thx bro

[AhYaOk]

great stuff! cool graphics too. did you use flash for that? it made it very easy to visualize. i never thought i'd say it, but the more i learn about math, the more i like it.

thank you!!

[videomathtutor]

No, just used graphics with transitions using iMovie. I hope to use keynote for future graphics so that they are even better.

[videomathtutor]

I don't know what you mean. Please be more specific.

[spiralfoxxx]

its amazing people know math but dont have an accurate view of math history!!!!

[CrimeTime12]

Greeks created algebro to make us suffer on school :P i am greek btw. XD

[videomathtutor]

Greeks did not create Algebra. As a Greek, you should know this.

[lightymoon]

@CrimeTime12 :Arabs created Algebra

[videomathtutor]

Arabs helped spread algebra, and I am sure made improvements to it, but algebra can be seen in earlier Indian cultures, plus Babylonia, and even China.

[DerrickDmx]

math is my worst subject in high school im trying to get A's so my GPA WELL GO UP

THIS HELPED A LOT THANKS

[willog666]

thanks for these videos.i allways got so stressed by maths as a subject.i feel like i can relate to it alot more now

[mrsmathmom]

Nice animation- I'm a math tutor and it's sometimes hard to get students to visualize in 3 dimensions. I will recommend your videos! Good stuff :)

[videomathtutor]

I am creating a special website for private math tutors. More details coming soon!

[spiralfoxxx]

ok guys the greeks got math and geometry from the egyptians /kemetians.... who had to learn it from ethiopians/kushites.....

[dgl1962]

These are excellent videos.

Your cadence is just right and even your voice is soothing,paced and allows one time to grasp the concepts being discussed.

At 47, I still enjoy learning geometry!

It would have been so much easier for us in the seventies with these online tools.

By the way,you can have a triangle that has a sum total of 270 degrees(interior angles)...

Spherical trigonometry.

Thanks

[videomathtutor]

Please assume all is Euclidean geometry, unless otherwise stated.

[andresblazeit420]

If the only information you were given about a trapezoid was the height and the first base's length, how would you find the length of the second base?

[videomathtutor]

You can't. You need to know what the area is.

[Mcdannyboy15]

this dude is probably a laid off teacher due to the fact hes on youtube teachin

[videomathtutor]

Nope. I am not a teacher. I am a professional math tutor. I make my living off my videos and doing private tutoring.

[thaprinceguy]

OMG! Thank you for making the video AND putting it on youtube. Im Krystal on my brothers acount, if not i would subscribe but your definatly going to favorites! I just started in a virtual school 'cuz I moved to Argentina and I have been out of school for a couple of months and i learned half of this stuff before i leaft but didnt get any credits so now i have to do it online. Thanx again. It brough everything back I really needed the auditory memory of the formulas. THANK YOU SO SO SO MUCH! :D

[homme925]

Hi, just wanted to say thanks, and keep making these videos. I managed to get by with out truly learning this stuff, but now the GRE is staring me down, and I can fake it anymore.

Cheers.

[jakepoop333]

That's a really great review. I wish I were still in algebra so I could put it to better use <_<

[savioroftitans]

luis,

I have a question.

when your dealing with angles on a plane and some of the angles are equal to for example"3x-3" while the other is like "6x", how do you find x?

thank you very much

[videomathtutor]

I talk about that (I assume you mean "triangle" not "angle") in the lesson: "Algebra: Solving Linear Equations - Part 2: Applications." The notes are for sale now, but the video is still being made. It should be finished soon.

[amoxtlacatl]

Luis,

I have a question.

When visually facing a scalene triangle, HOW do you determine which of the ALL the possible lines bisecting the triangle is THE height?

Thank you.

[videomathtutor]

Angle bisectors are not necessarily altitudes (heights). Any triangle has 3 heights. There is no single "official" height. The altitude is a segment perpendicular to a side (or its extension) that also intersects the opposite vertex. The height is the measure of the altitude.

[amoxtlacatl]

Much obliged. :)

[rockerresident]

thanks god i saw this video ..i was searching for geometry lesson... i've been watching all the algebra video of yours sir never knew u have goemetry..thanks

[avanbrown]

I love your videos. I am officially hooked. Do you have some thing on Probability and Stats.  Keep up the good work

[videomathtutor]

Not yet. I need to finish algebra videos first. Statistics videos won't be done for a LONG time.

[GaarasIchibi88]

Now, I need to prepare for my state test and yet I'm having problems with geometry, do you have any vids that you may direct me to? I pretty munch don't get all of it.

[videomathtutor]

Sorry, I don't know of any vids. I will be making some, but not right now.

[SonicReplay]

howmuch is that on Australia dollar??????

[videomathtutor]

Around $A31, I believe.

[SonicReplay]

Howmuch is your tutoring over webcam????????

[videomathtutor]

$25USD per hour.

[btkw]

Is there a written summary of all of these?

[videomathtutor]

Yes, visit my website.

[thavynator]

i love this video, thanks

[anon77xyz]

cool,thanks

[minggnim]

Excellent vid. Thanks.

[Bonescod]

hey listen thank you for putting this video up i have my finals next week and im worried i wont pass it so im goin to be watchin this till the day of the test thanks again

[randall12221995]

Hey thanks ur better then my math teacher =D

[dardaf904]

Hello my son is getting ready to take his ACT on June 13, 2009. Can anyone help with finding videos he can watch on youtube that will help him study for the ACT.

[videomathtutor]

He can watch my videos and you can hire me to do private tutoring using webcam (for a fee). I cannot recommend videos from others since I don't think they are very good.

[cyb3rb0t48]

I think it was arabic. An Arab created it and named it Al-Jabr. The europens got this.

[nicesooo]

Who invented (Algebra)?

[videomathtutor]

Some say the Arabs, others the Hindus and others feel the Chinese knew all about Algebra well before anyone else. You may want to check Reference web sites instead for a better answer.

[ararmaya]

Chinese?!? It seems your references do not go back as far.

[videomathtutor]

Huh? I don't understand what you mean.

[chemistrycoolguyscom]

do you teach grade 9 academic like these the academic i need to find these units -Review of Essential Skills

-Algebra

-Linear Equations and Word Problems

-Relations

-Analytical Geometry

-Area / Perimeter / Volume

[videomathtutor]

Yes, I can help you with all the above. Visit my website for more info on getting webcam tutoring.

[cdholder18]

Thanks, good review for my sats.

[videomathtutor]

I am planning special SAT videos, but not for a few months. I hope they can help you.

[SUBBY554]

thank you!!!!!!! this is gunna help alot on my tests

[videomathtutor]

I am glad it is **GOING TO** help you on your tests.

[iluvbluewhales]

soo nerdy....

[videomathtutor]

And yet... You watched it!

[tyrhhjy]

thanks for this. extreamly helpful!

[IBeThatCarsSon]

Thanks for the help

[IvoryGuru]

Thank you for this video I really helped me prepare for my math placement test.

[zetsushoren]

i got homework in math, can anyone help me?

1. the quotient of a certain polynomial and -7m(squared) is 9m(squared) + 3m + 5 - 2(over)m. find the polynomial.

2. suppose that a polynomial of degree n is divided by a monomial of degree m to get a polynomial quotient. (a) how do m and n compare in value? (b) what is the expression that gives the degree of the quotient?