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UmarsBack
 one year ago
What is the vertex for the function? (You will want to find the axis of symmetry first.) Write as an ordered pair, leaving no spaces, such as (1,4).
y = 3x2 + 6x
UmarsBack
 one year ago
What is the vertex for the function? (You will want to find the axis of symmetry first.) Write as an ordered pair, leaving no spaces, such as (1,4). y = 3x2 + 6x

This Question is Closed

Eyad
 one year ago
Best ResponseYou've already chosen the best response.1use the square to convert to a vertex form ,y=a(xh)^2+k

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2I guess we're not making sense, @UmarsBack

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0you really arent :c idk what im suppsoed to do.

Eyad
 one year ago
Best ResponseYou've already chosen the best response.1its like : ax^2+bx+c the vertex is on the axis of symmetry: b/2a when x= b/2a we find y in this case 3x^2 +6x +0 gives us: a=3 b=6 so when x=1; we get y= 3+6

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0So what i gotta do? sorry for my stupidity.

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2okay let us do some reading ..

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2http://finedrafts.com/files/math/precal/Larson%20PreCal%208th/Larson%20Precal%20CH2.pdf

Eyad
 one year ago
Best ResponseYou've already chosen the best response.1x=b/2a in this case 3x^2 +6x +0 gives us: a=3 b=6 Which mean x=6/6= +1 ! y=3+6= 3 Vertex = (1,3) =============

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Im completely clueless guys.

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2can you read pp 126131?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2I just want you to be acquainted with the terms and definitions

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Yes im reading right now. again, sorry for my stupidity.

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0@nincompoop im doneee

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2so what did you learn?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2eyad's information should make sense by now...

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Quadratic function = f(x) = ax^2 + bx + c

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2yes, that is the format of your equation at the moment. now, to help you identify the vertex of the parabola (graph of quadratic) you need to covert it into standard form of quadratic function

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2your vertex then is going to be the h and k

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2there are a few things you need to be good at like completing the square and factoring so you can solve this even mentally

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2do you know how to complete the square yet?

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0wheres the h and k? and no :c

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2hehe this is going to be tough… so even eyad's info doesn't make sense right now?

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Im tryna understand >_<

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0should i go to khan academy?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2you can, but it's in the textbook and eyad pretty much gave the answer already

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0you know i hate reading lmfao. i read the text book tho. im brain dead right now.

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2okay let us try this the long way so you understand the whole concept quadratic function f(x) = ax^2 + bx + c; f(x) is the same as "y" so this is what you have: y = 3x2 + 6x; this is the same as y = 3x2 + 6x + 0 (the equation you were given has + 0 omitted) this means that: a = 3 b = 6 c = 0 I need to know that you read and fully grasp this part

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Omfg i understand it way more now.

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2good, now recall the figures in the text book about vertex? I attached it so you can recall them

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2good! we are making a progress here. keep in mind about vertex being either the lowest point or the highest point lowest point if a>0, which means the parabola opens upward highest point if a<0, which means the parabola opens downward the reason I want you to keep this in mind because the terms minimum and maximum give you the same definition in terms of the value of a recall your equation:y = 3x2 + 6x does this mean that your parabola opens upward or downward?

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0The parabola opens upwards?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2I want you to be certain of your answer. Only when you are confident that we are able to move on…

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2I made the figure bigger so you won't miss any detail

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Its downward. right?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2with your equation y = 3x2 + 6x I mentioned this: a = 3 b = 6 c = 0 and I also mentioned this: lowest point if a>0, which means the parabola opens upward highest point if a<0, which means the parabola opens downward ask yourself this question: is the value of a less than or greater than zero? greater than zero gives you an upward parabola less than zero gives you a downward parabola

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Its upward, because the value is greater than 0

Eyad
 one year ago
Best ResponseYou've already chosen the best response.1Btw @nincompoop ,After you finish you may Compile all your comments and post it in a one post ,IT would be a good tutorial Including the example .

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2awesome! now you seem more confident. now, let us move on understanding the standard form of a quadratic function I attached some information for you to reread (since you said you read it earlier)

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2keep in mind that the values of your a, b, and c have not changed. they are still a = 3 b = 6 c = 0

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Okay im still with you.

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Okay continue. youre the teacher here.

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2now, we need to try to rearrange your y = 3x^2 + 6x into the standard form of quadratic function, we can achieve it by completing the square, which for now will look like: factor 3 out of xterms \[y=−3(x^22x)+0\] I included the value of c for the purpose of showing you what it would look like, but since our c is zero we can ignore it. do you know how to proceed or know how to complete the square?

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0I dont know how to complete the square :c

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2it is now the time to learn one way is to divide the value of b by 2, and then square it but things could get more complicated than that so you will need to read and familiarize yourself http://www.mathsisfun.com/algebra/completingsquare.html or this http://www.purplemath.com/modules/sqrquad.htm

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.06/2= 3 2(3) ? like that?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2yes, remember that you have to square it after you divide it by 2

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2so \[\left( \frac{ b }{ 2 } \right)^2\] \[\left( \frac{ 6 }{ 2 } \right)^2=3^2=?\]

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0It equals the same thing right? 6?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2\[3^2=3\times3=?\] to square is to multiply the multiplicand by itself twice

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2so your multiplier is also 3

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2did you read the contents of the links regarding completing the square I provided earlier?

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Not yet. let me read it now.

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0x2 + bx + (b/2)2 = (x+b/2)2 < thats how you complete the square?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2so this is where we left off: \[y=−3(x^2−2x)+0\] we need to complete the square of what is in the parenthesis our b is 2 \[\left( \frac{ 2 }{ 2 } \right)^2=1^2=?\]

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2WAKE UP!!! 1 multiplied by itself is 1 this is what we will yield: \[y=3(x^22x+11)\] After adding and subtracting 1 within the parentheses, you must now regroup the terms to form a perfect square trinomial. The 1 can be removed from inside the parentheses; however, because of the 3 outside of the parentheses, you must multiply 1 by 3 this is what it would look like: \[y=3(x^22x+1)3(1)\] 3(1) = 3 if you are still with me, we just solved the value of k this confirms one of @eyad's solution earlier k being 3 next step is to factor what is in the parenthesis \[(x^22x+1) \] turns into: \[(x1)^2\]

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2can you guess the value of h?

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2that is super awesome! our rewritten quadratic function form looks like this: \[y=3(x^21)^2+3\] \[y=a(x^2h)^2+k, where: a \neq0\] vertex: (h,k) ((1), 3) or (1,3)

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2does this look like eyad's answer?

UmarsBack
 one year ago
Best ResponseYou've already chosen the best response.0Hahaha wo i cant believe i understand this now. it looks like eyads answer. thanks alot nin omfg.

nincompoop
 one year ago
Best ResponseYou've already chosen the best response.2btw a few notes to consider: \[1^2 = (1)^2=1\] earlier, I should have typed \[(1)^2=1\] \[1\times1=1\] negative multiplied by a negative yields a positive

Eyad
 one year ago
Best ResponseYou've already chosen the best response.1A good teacher can inspire hope, ignite the imagination, and instill a love of learning.
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