Determine whether an equation determines y as a functions of x

[@AkronOhioKid]

I got a 45 on my test, but it would've been a 0 without your help. Thanks man

[@brianmclogan]

no worries man, keep working hard, you can do it, do not let one bad grade define you or get you down

[@goodmusic698]

you had me in the second half not gunna lie

[@ALLvideogamesFANBOY1]

lmaoooo

[@djevlinelouis6934]

😂😂😂 story of my life

[@jennifercope7765]

@@brianmclogan o

[@yussefaboud6519]

9 years ago and i’m now here, this guy left a footprint on earth that helps generations of kids that’s impressive

[@brianmclogan]

Yes! I have all the videos you should need in your class. Three years running making videos. Happy to help!

[@galaxyboy6127]

12 years later and he’s still help people 💀 (bro saved my grade)

[@e.m.janssen3638]

Eleven years later and this still really helped me, thanks very much.

[@sebastianmunoz9871]

Nearly a decade later and this man still helping people out

[@moreliaballi1970]

so basically what he meant was that everytime you have an y^2, it will not be a function because y is not allowed to be squared, only the x can.

[@brianmclogan]

correct

[@shirbear9367]

Thank you so much for that comment I'm struggling on one problem for hw

[@Zeeviex]

Morelia Balli may the lord bless your soul.. thank you

[@jennykalove]

i love you

[@jacobpowell2400]

what that means is the parabola gets turned sideways and that's not allowed

[@brianmclogan]

you are welcome! happy to help.

[@brianmclogan]

you had me a bald guy! : ) c'mon it's shaved head, there is no loss of hair. haha really happy to help you out. Keep up the hard work, bald man is a working.

[@brianmclogan]

okay since y is squared you will have to take the square root on both sides to undo the operation. Therefore leaving you with a positive and negative value of x. Y cannot be defined as a linear function of x. This can only be done when all exponents on variables are raised to the first power and no two variables are multiplied by each other or appear in the denominator. Does this help?

[@ujust]

So is it safe to say that if your y value has a square in it will not be a function?

[@brianmclogan]

no if it just y then the answer would be 8 since it is y squared we have to take the sqrt of both sides

[@brianmclogan]

Do you have a question I can help you with to better understand? Sometimes shy, sometimes not, depends on my mood i guess

[@briisanai]

hi my assignment is due at 11:59 , really need help . does the equation xy + 3y = 6 define y as a function of x?

[@brianmclogan]

you are very welcome! happy to help

[@brianmclogan]

can you reprint that problem again this is what I think you are asking y^2 = sqrt(x+2)? Is that it or what is the problem again?

[@priscillacoral2559]

So pretty much every time you have to use the square root then the answer will not be a function?

[@brianmclogan]

yes because there are two solutions the positive and negative, and a function can only map to one solution

[@diona5370]

y=radical x^2 -1 is a function, why?

[@kellyiprado]

@@diona5370 in that case you know that the radical is positive, the function itself already gave you that information. I think that's it, not sure but it's an idea

[@pdisp]

@@kellyiprado You're right.

[@yutanakamotobestie6531]

What if it’s a cube root? Or fourth or fifth?

[@boopers89]

On the first problem if you subtract x , could it be y= 9-x or does it have to be y= -x +9 ... Thank you

[@brianmclogan]

no worries, happy to help!

[@theignorantgamer4357]

This man has literally come to the rescue for me...a week late in college classes, you're the best man

[@brianmclogan]

happy to be able to help you

[@experiment0003]

Thanks.. very helpful. Get a glass of cold water please.

[@younel6364]

Yo is that you in pfp bro cuz you faded bro.

[@MsSummer213]

So what if (on the second problem) the y isn't squared? Do you still use the square root and get a +- out of the answer?

[@brianmclogan]

what is your original equation?

[@Jabbawockeez416]

Just 1 question, if I have y^=(squareroot)x+2, which is similar to your second one. How would I know if that is a function or not

[@salimamansoura7838]

May God reward you for all your efforts and all the valuable information you easily provide to us .

[@hadezmage]

Hello!I received two questions that say to determine y as a function of x (or not). I'm attempting to solve these two and ran into some problems. Well, the first question is y = x² ± 3. How would I go about solving the problem with a plus/minus sign? Does that mean I will have two answers? Do I solve it normally? And the second question: x = 12 - y. Would I subtract 12 as to get y alone? But, if I do, it will be "-y = x-12" Then how would I deal with that negative sign?

[@brianmclogan]

1.) yes you have to solve it twice for +3 and -3 for any value of x you will have two answers, so it is not a function of x. 2.) yes you have to solve for y not -y so divide by -1 on both sides to obtain y

[@Ashton_Loomis]

I got a 97% on my test! Thank you so much.

[@TeamJacobAndPaul1]

Oh, my goodness!!!!! Thank you so much!!!! You have no idea how much this helped me!!!! I'm in Trig and PreCalc and we just learned this today, and I had NO idea how to do it. It turns out that my math teacher taught us this same thing, just in a WAY more complicated way that I didn't understand at all. BUT, then I watched this, and I completely understand now!!!! THANK YOU SO MUCH!!!! You just saved my life :D

[@brianmclogan]

TeamJacobAndPaul1 you are very welcome! I taught pre-calculus the last three years recording videos everyday so I am sure I will have plenty of videos throughout the year to help you out. Just check out my playlists, website or search my channel. If there is anything I can do for you throughout the year just let me know. I am happy to help!

[@DPStudios]

Another video from you that explains it better than my college textbook (that sometimes doesn't even attempt to explain it). Thank you!

[@jlamar4life]

Determine whether the equation define y as a linear function of x. If so, write it in the form y=mx+b. 4x - 7y2 + 6 = 0; **the 7 is y to second power...exponent.

[@aleear0199]

In regards to the second equation, wouldn't the answer not exist? You dropped the negative in continuing to solve the equation. The square root would have been taken from -x^2 not x^2. Does this change the result?

[@shakilumair7818]

can u help me to solve it ? Determine whether y would be a function of x. a) 𝑦 = grade you get on an exam 𝑥 = number of hours you study . b) 𝑦 = a person’s weight 𝑥 = number of minutes exercising per day.

[@ewankosayo5474]

how can we know what is the domain and range if its function?

[@isabellemartinez9305]

would x^2 -7y=3 and x + 2y=6 be functions ?

[@moomoomeu9235]

What if its x + y^3 = 8? Is it a function?

[@sajooj7948]

Hello I was wondering if y is a function of x in this equation y^3-3x=8 why or why not

[@elf9064]

The problem I'm working on is y=4x(squared) I thought it wasn't a function because of the square after the X, but the answer key is saying that it's a function. I'm confused.

[@brianmclogan]

every value you enter for x produces one value for y so it is a function, in the example of this video every x has two y values

[@christianborjas8648]

How many times has this man saved my life? Too many to count lol

[@lucasolimpio4443]

Thank you for the explanation. Please Teacher, could you help me with this following exercise? Solve the equation in integers: x^2- 5y^2= 5. I'll be very grateful.

[@Chumbama]

You should provide more examples than just the most basic ones. 2x-5y²=2 4|y| -5x²=2

[@brianmclogan]

I Love Ariana's Music I try to include basic and advanced problems for all of the math I teach. Will try to include more videos like this for you

[@Chumbama]

I'm confused by the problem with absolute value for y that i mentioned in my previous comment. And if x is squared can it still be a function. Thanks for helping your a better tutor than the ones at my college.

[@brianmclogan]

I Love Ariana's Music basically y is not a function of x when you solve for y there are two cases. In the first example there are two cases for y because when you take the square root you have to include the positive and negative values of x. In the second example when you solve an absolute value equation you also have to take the positive and negative values of x so in both instances y is not a function of x

[@brianmclogan]

great, glad i could help

[@germenfredrickajeno9270]

What if y^3 - 4= x ?

[@tankfire20]

when you subtract x^2 on both sides won't you get plus minus i when you square root both sides?

[@brianmclogan]

not finding any values so no need for i, just seeing if we can write y in terms of x as a function

[@ayesir260]

So basically y is a function of x as long as it doesn’t have two solutions? Doesn’t matter what y equals to as long as it wasn’t squared in the beginning?

[@sabilakhan82]

how is it possible sir we already studied that for a given domain we can have two values of y(by the definition of onto function)...

[@brianmclogan]

This is not a function

[@MsSummer213]

Where did the 8 come from?

[@desab6]

my favorite bald guy!!! u just saved me thanks so much!

[@matto2971]

What allowed you to get rid of the -x +1 and make it x+1?????

[@SYN420]

Awesome!! I always get stuck on these problems!

[@noor-qq4zc]

genuinely saved me you're amazing

[@matthewjames1378]

thanks a lot m8 the video helped me, I have my algebra test in 2 days.

[@javib8439]

And what about the domain and range?

[@brianmclogan]

+JaviB I have other videos explaining the domain and range of a function

[@paulnovak6977]

The domain is the x value and the range is the y value. A year late by free help

[@lydiaq8324]

so if anything is y^2 or x^2 or anything squared, its not a function?

[@brianmclogan]

Hanel Marks no, only when y as the dependent variable is square it is not a function

[@lydiaq8324]

Okay, I understand now. Thank you so much!!

[@brianmclogan]

your welcome!

[@victorianguyen3919]

is 2x^2 + y^2 = 5 isnt a function right?

[@brianmclogan]

correct

[@olivergalindo183]

so it needs to be a one-to-one equation?

[@idontevenknow2444]

So x= any number Is also not a “y is a function of x” answer?

[@themanagement69]

I don’t even know use vertical line test, x=any number fails infinitely at that number

[@constarrZ]

thanks. Cleared that up for me on my math homework

[@JacobZubahDukuly]

Alex was not able to make me understand, Sir. Thank you so much.

[@Poloboyy.c]

Man ate a peanut butter sandwich before teaching😂

[@moomoomeu9235]

So if y is ^ to any number does it mean its already not a function? Plsss answer i have an exam tomorrow and im really struggling😭

[@ChromaticaCitizen]

I’m taking thiscollege algebra class and we use ALEKS. The ALEKS program did not explain it this simple 💀

[@ChromaticaCitizen]

Thank you so much for explaining it so much easier!

[@murm42]

This video helps a lot to explain whether an equation determines y as a function of x. thank you so much

[@Ha1iFaX]

so if it has a y^2 then it can't be a function of x?

[@cindyhoward9276]

Please use darker markers! Good job!

[@kit-kat2300]

What do I do if it’s a cube root

[@maximillianmoffett]

im so confused by your example. given the square root or x^2+1 why can you not just take out the square root giving you x+1? it makes almost no sense to me that you would have to keep it the way it is. and also is that the case for a cubed root as well?

[@brianmclogan]

I am not sure exactly what you are saying but what I believe you are trying to do is not mathematically allowed as it does not work for all numbers. Try replacing x^2 with 9 which is 3^2 and see if it works out numerically

[@maximillianmoffett]

yeah it would work I think? the only question I am asking is why you did not simplify the square root of x^2+1 to x+1? any number you plug in would work because x is raised to the power of 2

[@brianmclogan]

sqrt(x^2 +1) does not simplify to x+1

[@HelloHello-vq5fw]

Can y be raised to an odd power and be a function

[@brianmclogan]

yes

[@brianmclogan]

correct

[@kentagent6343]

But why does my book say that x^2 + y^2 = 0 can be written as a function of x?

[@DrGeorgeOMalleyRules]

Thank you! This made waaay more sense than when my professor explained it.

[@brianmclogan]

+Brianna L happy to help

[@veronicabekee]

You look shy.. Didn't really understand it tho.. But knew what u were saying.. At least now I know alil about this math

[@liliannag6024]

Wait but what does y=3^x mean?

[@brianmclogan]

3 repeatedly multiplied x times

[@jnimieee7049]

Thank you po God Bless po😇

[@musaconteh1032]

Thank you for the brief understanding.. really helpful..

[@axlotle]

OH MY GOD. THANK YOU THIS IS SO HELPFUL!!!

[@brianmclogan]

happy to be able to assist you

[@kathywible5401]

does this mean that anytime there is a exponent of 2 that it is not a function ?

[@brianmclogan]

because to solve for y you have to take the square root to get rid of the exponent of 2. when you take the square root you have the positive and negative answer. Since you have two answers it is not a function

[@jlamar4life]

Okay, Mr. McLogan, I have solved my equation. But, I still don't know or understand if it should be -y2 = -4x - 6; Therefore, y is not a function of x....OR should it be to solve the previous equation further and now say y=4x+6 and IS a function of x. Please help. I don't want to cheat. I just want to understand. I am SO LOST.

[@gavriellepineda3855]

if y has an exponent of 3 is it still a function?

[@brianmclogan]

yes

[@savannahjones9716]

Thank you so much! I could not understand why or why not y would be a function of x, but now I actually get it.

[@cheyenner8691]

Is y=x^3 a function and you can explain?

[@brianmclogan]

yes any value of x you insert into the equation will give you one unique value for y

[@jakegregory4640]

Three lectures and didn’t understand this bc my professor moved to quick and talks like a librarian. Thanks

[@kevinmendez7818]

What about y=-x

[@jaynicolediscoverys8410]

what about x < 4y...how do I solve for that?

[@brianmclogan]

what are you supposed to solve for, you have two variables so your answer will have another variable in it.

[@jaynicolediscoverys8410]

I supposed to determine whether or not y is a function of x and whether x is a function of y.

[@brianmclogan]

okay will that is an inequality so it is not a function of x or of y

[@jaynicolediscoverys8410]

Y^2+2y-x=4

[@jaynicolediscoverys8410]

Nd ^^^^that is to determine the same thing

[@nemesis8265]

scared for my pre-calculus test tomorrow, wish me luck!

[@daisybello729]

its 2022 and i watch your videos

[@brianmclogan]

Happy to help!!

[@alexandragarcia2786]

what if y is a negative?

[@CrystalinRose]

So all in all, if it has 2 answers for y, then it's not a function of x

[@miralove791]

I'm pretty confused how is radical 4 equal to 2 and at the same time equal to -2 you didnt say the point only if there is "-" out of the radical it becomes -2

[@brianmclogan]

+Mira Love is your question in the context of the video? Or from another problem?

[@miralove791]

+Mr. McLogan's Math Channel 1:41 u said it but anyways i get it now :D

[@brianmclogan]

+Mira Love i see, okay, let me know if you need further clarification

[@miralove791]

+Mr. McLogan's Math Channel one last question im struggling with Binomial Expansion finding the constant term i basically don't get it. I don't know if there is a formula to find the the constant term after we expand or what . ( i know its out of topic ) i need an answer 'cause i have my algebra exam Tommorow and I'm grade 10 btw

[@brianmclogan]

+Mira Love well the quick rundown is to expand binomials using foil, (x+a)^1, (x+a)^2, (x+a)^3 what you will notice is the coefficients of each term follow a pattern. Better known as Pascals Triangle. This works for any binomial. Try foiling the four binomials I gave you and compare them with Pascals triangle. Rather that further expanding binomials you can use pascals triangle to identify the coefficients or multiple of coefficients based on the power the binomial is expanded to. I have videos if you search my channel. Hope they help, let me know if you have further questions

[@jaynicolediscoverys8410]

×=y^2+4 would not be a function?

[@brianmclogan]

correct

[@aminehr776]

PLZ HELP! I can't solve this problem. X=-y^2+2y+1 I can't find the y-value.

[@brianmclogan]

amineh r set x=0 and then solve by factoring

[@aminehr776]

Mr. McLogan's Math Channel yes I understand that but I get two y values so how do I know if it is a function of x or not

[@brianmclogan]

that is different question then solving and since you have two values when you solve it is not a function of x

[@Wires747]

is y=√x+3 a function and why?

[@brianmclogan]

yes every x value has a single unique y-value

[@Hudvoltz]

wish you were my precal teacher rn

[@gabrielaleon2603]

okay so YOU HELPED ME BIG TIME FOR THIS QUIZ BUT i dont get the f(x) crap for my practice problems if im solving for Y

[@brianmclogan]

just think of the f(x) as y for simple purposes

[@KUGO-ro9ff]

Why does it become a plus minus tho?

[@Maeve-i9j]

would y=|4x-18| be a function? what about |y|=4x-18

[@brianmclogan]

yes, no, graph them an apply vertical line test to confirm

[@kayla3441]

Thank you! This helped a lot!

[@brianmclogan]

awesome! happy to hear

[@williamosorio4293]

is y=|x| a funtion?

[@brianmclogan]

yes

[@fidelisbekong9954]

Thanks a lot, funny how my professor won't explain this as easy as you do.

[@brianmclogan]

happy to help!

[@marceliusmartirosianas6104]

x^2+y^2=2 x+y=1 xy=1 X=O y=1 ACADEMIC Marcelius Martirosianas

[@ashwinsivaainkaran202]

This teacher is litty 💯

[@brianmclogan]

cheers Ashwin!