Question

Write the quadratic function in the form
f(x) = a (x-h)^2 +k
.

Then, give the vertex of its graph.
f(x) = -3x^2 +12x - 14

Answer 1

ok so I know how to do the second part now I'm pretty sure but what is the first part referring to exactly? oh and this is my last one!!! @jim_thompson5910

Answer 2

so make up some numbers for a,h, and k is all it is asking

Answer 3

oh oh strike that last

Answer 4

so it wants you to complete the square(factor) the function so it looks like the vertex form for a parabola

Answer 5

so the second part I plug in to here to find the vertex right?

\[(-\frac{ b }{ 2a },c-\frac{ b^2 }{ 4a })\]

Answer 6

complete the square in order to learn this better

Answer 7

ah... well, if you complete the square, you know the vertex.

Answer 8

because it is (h,k)

Answer 9

you find the the vertex by completing the square

Answer 10

you don't need that(nor do I know if it's right, too many formulas to memorize)

Answer 11

i never memorized any formula in math, just learn where things come from

Answer 12

completing the square is where it came from so no harm in bring the it back to play the role :)

Answer 13

I'm not sure what the square is exactly I've had like 6 questions like these so far but before this " see what you know" quiz i had never learned this stuff before so I'm still trying remember how this all works

Answer 14

\[\huge y=a\overbrace{\color{red}{(x-h)^2}}^{\text{this is the square}}+k\]

Answer 15

\[f(x)=-3x^2+12x-4=-3(x^2-4x)-4=-3(x^2-4x+4)+12-4\]
\[=-3(x-2)^2+8\]

Answer 16

that how you complete the square

Answer 17

I walk away for 5 minutes and you're already just giving answers x, for real yo?

Answer 18

so vertex (2,8)
the graph open down

Answer 19

hehe she said still have more question similar no harm to learn from this example seeing how it is worked completely

Answer 20

This is her last one haha

Answer 21

hehe well i read in her replay she has 6 more or something
at any rate, my intentions are clear :)

Answer 22

this is a see what I know quiz lol so I'll be learning it more in the lesson I just didn't want to do terrible on it

Answer 23

method 2
compute \[-\frac{b}{2a}=-\frac{12}{2\times -3}=2\] then go right to
\[y=-3(x-2)^2+k\] to find \(k\) replace \(x\) by \(2\) in the original equation

Answer 24

much snappier imho

Answer 25

oh bad bad please don't look for your quiz answers like that
if i knew you wouldnt get any answer

Answer 26

I have been working on this for about 10 hours straight though so my brain is also like fried at this point so I really!!! appriciate the help @misty1212 @xapproachesinfinity @FibonacciChick666

Answer 27

lol it's ok, I'm gonna let you explain,also I'm mad cause this is a quiz(even if it's not a summative assessment). I'm tired.

Oh old age, how the body doth wither and groan in the wind and sun day after day. For thou shalt know the pain of mountains, as they slowly crumble and fall upon death.

Answer 28

I promise I've watched youtube videos I've read multiple explanations and looked up tons of formulas My intentions were and are not to just be given the answer out of laziness

Answer 29

ten hours of math?

Answer 30

go have a glass of wine

Answer 31

yes I've been working on it alll day literally! lol

Answer 32

that's some quite a language lol

Answer 33

next semester it will all be different...

Answer 34

lol thanks x. And even with good intentions, it still gets a reprimand in my book. Finally, watch the khanacademy.org lessons, they will save you from 10 hour days. Take the assessment quiz, don't look anything up while taking it, and then watch from where it sits ya at. You'll then understand the material a heck of a lot better especially if you are a nontraditional student.

Answer 35

khanacademy were some of the videos I watched. I honestly with all due respect do not see the problem with also having help and things explained through here and how it's different than watching a video or reading any other explanation some I needed help being guided through and to be pointed in the right direction or to have my answers checked to make sure they were either right or I was on the right track. Regardless I have had a long night so I appreciate the help and opinions have a good night