write an equation of a parabola from a given graph 

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You covered more in this video than my math teacher does in a full hour and a half 😂

I wish this man taught all my classes

This is the first person I've known who does 7 hours of math on there bday.

Your dexterity at the white-board is phenomenal and your explanation is clear, concise and completely convincing: thank you.

I'M NOT EVEN JOKING. I HAD AN ASSIGNMENT DUE AT 12 AND THANK YOU THANK YOU FOR HELPING ME UNDERSTAND THIS STUFF lol

Thank you very much! I was struggling with my physics homework because I forgot how to write the equation of a parabola. This really helped me. :))))

Very Helpful! I think this is exactly what I've been trying to figure out, and it was explained very well!

Thank you so much! This was very helpful and your explanation was very easy to follow!

Another way to do this is to set Y = a(X-b)(X-c) and find a, b and c. Note that if X= b and/or X = c we have Y = 0. So take b = 1 and c = -5 and you end up with Y = a(X-1)(X-(-5)). In order to find a you should require that one of the points (0,5) or (-2,9) is on the graph. Substitue for X = 0 and Y = 5 and you see that 5 = a(-1)(5) or 5 = -5a. This gives you a = -1. The equation is Y = - (X-1)(X+5). This, of course, is identical to the solution in the video.

thank you so much, you explained it so much better than my actual math teacher:)

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thank you for the basic break down, you simplified it more that all my teachers did through high school.

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Thank you so much for this lesson, it helped me so much and I could understand everything perfectly

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this came in clutch, i literally have an exam about this in like no time

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omg I was the 1500 like exactly and this video was super helpful I understood it super well thanks to the video

If we are not given the points on y axis then how can we make the equation..?

Thanks you answered all the questions I had about this without having to struggle to raise my hand

vertex is [-2 , 9] (v = h , k) y intercept is [0 , 5] x intercepts are [- 5 , 0] and [1 , 0] We have a "frowning" parabola. so we know that a is of a negative value So the vertex formula is y = -1(x+2)² + 9 (vertex form is y = a(x-h)² + k) The quadratic formula is y = -x² - 4x + 5 We know the a term is -1 because of the formulas x = h + √(-k/a) and x = h - √(-k/a) so lets prove it: x = -2 + √(-9/-1) negative divided by negative is positive so that means √9 which is 3 so x = -2 + 3 and x = -2 - 3. or the x intercept is the xy coordinate [1 , 0] and [-5 , 0] which is true for both cases. now prove the quadratic form: -1(x+2)(x+2) + 9. gives us -1(x² + 4x + 4) + 9 which finally is -x² - 4x -4 +9 or -x² -4x + 5 In order for there to be x intercepts the k term MUST be either the opposite sign of the a term OR k must equal 0. (otherwise you are taking the square root of a negative number. imaginary is ok for solving the equation, but it does not translate to the graph and it shows there is no x intercept) Made a couple mistakes and only caught them because I proved my equations. Always prove and show your work. If your teacher is worth their salt they will see where you are coming from and may advise you of where you messed up. Anyways it has been a long time since I've done this stuff and I only do them for fun to keep my brain sharp.

I never thought I'd be using parabolas to optimize my builds in a video game, but here I am, lmao.

thank you sir

Thank You !!!

Thank to so much for this explanation!! 🙌

Helpful

Thank you broo

Super helpful video. Thanks a ton!!!!

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he taught it less than 10 minutes amazing!

This was SOOO HELPFULL

Hello , thank you so much for the help man

Thank you man, Sincerely.

U made this so easy thanks keep it up

mans marker switching skills tho😹😹 But well explained m8🙌🏽🙌🏽

Very clear! Thanks mate

I'm kinda confused if you don't know the number for h (x coordinate for the vertex). How would you complete the vertex formula?

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Thank you!

thank you so much. Its very helpful

Thank you man❤

Thank you so much

Awesome video helped a lot

In the beginning I wasn’t understanding and in the end it seemed like I was in the beginning

super helpful. thank you.

Good job 👍👏

THANK YOU sooooo much you just helped me not be screwed on my math project🫡

what if the graph doesn’t give you the vertex value?

Thankyou soo much 😢💖

THANKYOU SO MUCH!!

Thanku

thank you!

thank you very much and how could one get the focus and the directrix from an equation in vertex form

thank you

AWESOME!!!!!!!

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Man Is literally giving me 5 head math power

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if the vertex is at the origin (eg, coordinates 0,4) is 0 still h and k still 4 or does it change?

The explanation is simple but my assignment is something else😢

omggg i get it noww

best

@Jan pumphrey yer teacher prolly isnt asian lmao there the smartest

Thanks baby 😘👌🏿

You did not helpp

Please Put away microphone it is too annoying

As a parent trying to assist her online math learning 7th grader THANK YOU! Your explanation was perfect and you showed every step.

Thank you so much

Thank you!!

broo this man makes it look sooo EAASY.. And my teacher em doing some calculas type of shit to find the vertex.. LOL

Thank you this was very helpful, especially when you explain where the numbers came from when writing the equation itself at the end.

I was struggling to understand the material until i found this video, thanks a lot 😂🙏🏽

Thanks very much..your explanation is very very clear ❤

Thank you. I know you produced this video 6 years ago and your teaching skills have improved immeasurably. However, I think it would have been helpful if you explained that you tackled the problem initially by completing the square, as most of us would be more familiar with this approach when asked to write down the equation, given the turning point/vertex (or vice versa). Otherwise, well done and keep up the good work.

In Search of gold I got diamond

srsly thank you so much, i was having such a hard time understanding, and i understood perfectly in this video

You taught me more in 4 minutes than my teacher could in four days, thank you so much

excellent, simple and smart explanation.

Thanks

Yes but in the case that I have the equation but not the parabola what can I do??

I have similar questions like this. But the turning point (vertex) is not given. How can I find that without the equation only from the graph?

Thank you so much this really helped me with my math

Wait, my teacher said that you cannot have a negative sign of the value of a, but if it is negative sign, you need to change the sign of all value. Im so confused 😭🙏 Please answer

bro, I have been struggling to solve these damn problems, but you saved me!!!!!!!

Damn i met this question a while ago and i used my own method which was to multiply (x+5) with (x-1) to construct the quadratic equation

Thank you, great explanation.

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anyone else here cause they don't understand maths ?

thank you, u helped me alot

Lol, im in a text (online) and using this video. Shhh

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Bringing me out the mud fr

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Thank you! Gracias

Thank you so much.