Question

What is the equation, in standard form, of a parabola that contains the following points?

(–2, –20), (0, –4), (4, –20)

Answer 1

I know \[y=ax^2+bx+c\] is the standard form for the equation.....

Answer 2

I don't know why it has the diamonds but the points are: (-2, -20), (0, -4) and (4, -20)

Answer 3

is this word question?

Answer 4

You need to solve three simultaneous equations. The first is\[-20 = (-2)^{2}a+(-2)b+c\]

All I did was substitute y with -20, and x with -2 from the first point (-2,-20). Do the same with the next two points and solve the three equations for the three coefficients a, b, and c.

Answer 5

its a workpad :'( so I haveta show all work.....:( I forgot how to do this :/

Answer 6

okay so:
\[-20=(-2)^2a+(-2)b+c ; (-4)=(0)^2a+(0)b+c ; -20=(4)^2a+(4)b+c\] right?

Answer 7

ok hold on

Answer 8

Sorry it took so long....I had to go do something for my mom....:/

Answer 9

y = ax^2 + bx + c

-20 = 4a - 2b + c
-4 = c
-20 = 16a + 4b + c

4a - 2b + c = 16a + 4b + c
4a - 2b = 16a + 4b
-6b = 12a
b = -2a

-20 = 4a - 2b + c
-20 = 4a + 4a - 4
-16 = 8a
-2 = a
b = 4
c = -4

y = -2x^2 + 4x - 4
y = -2 * (x^2 - 2x) - 4
y = -2 * (x^2 - 2x + 1 - 1) - 4
y = -2 * (x^2 - 2x + 1) + 2 - 4
y = -2 * (x + 1)^2 - 2

Answer 10

lol i answered this on yahoo

Answer 11

with a help of friend

Answer 12

@haleyelizabeth2017

Answer 13

I have to have the steps :( Like I need to explain them....I think I can figure it out though

Answer 14

i did give you steps lol

Answer 15

I meant I needa make the explanations haha :P

Answer 16

-_-

Answer 17

hey

Answer 18

yo

Answer 19

you aint no nig ga so stop acting like 1 :P

Answer 20

wtf???

Answer 21

:O IM CALLING A MOD HAHAHA JK :P

Answer 22

you the one sayin bad things!

Answer 23

O NO YOUR THE ONE MADE ME CRY SNIFF SNIFF YOu HUT MY FEELINGS WITH UR BAD WORDS

Answer 24

hurt

Answer 25

how????????????? I said yo den wtf.....I never said it. It could mean when to freak :P

Answer 26

MHMM LIAR :P

Answer 27

MOD MOD MOD

Answer 28

lol you are making me die i just cant stop smiling

Answer 29

shut up. buhbye!!! im not talking to you for rest of day

Answer 30

NO NO NO SORRY NO PLEASE :'( but fine!IIF YOU WANT LEAVE ME AGAIN ITS NOTHING NEW!!!

Answer 31

:P

Answer 32

i am trying so hard to be mad i just cant :/

Answer 33

but seriously sorry :(

Answer 34

haha

Answer 35

WHATS SO FRUCKING FUNNY

Answer 36

your face :P jk jk

Answer 37

>:( FU CK OS

Answer 38

IMA GO GET BANNED

Answer 39

Ill include you in chat :P

Answer 40

NOOOOOOOOOO Ducky you :P jk jk

Answer 41

lol

Answer 42

ok ducky me :(

Answer 43

k bye :'(

Answer 44

I SAID BYE!

Answer 45

huh?

Answer 46

geez la fwucking weeze

Answer 47

loser buhbye!!! :P

Answer 48

thats it!!

Answer 49

Do ya even like me or do i bother you?tell me huh?

Answer 50

ya thats what i thought

Answer 51

:/ bye haley and to save you from being pissed ill leave you alone!

Answer 52

huh? i was reading! calm down!

Answer 53

Ok just answer the question if im bothering you just tell me

Answer 54

nope

Answer 55

you sure :/

Answer 56

yup

Answer 57

ok but just block me if i annoy u ok?

Answer 58

okay :P

Answer 59

but lemme know before u do lol

Answer 60

so i can change ya mind

Answer 61

heehee

Answer 62

lol

Answer 63

That isn't right.....:( I don't think