Question

http://prntscr.com/l5h9r7

Answer 1

@Vocaloid

Answer 2

hint - which choice has a coefficient with a greater absolute value than 1/2?

Answer 3

C?

Answer 4

good so C is your solution

Answer 5

http://prntscr.com/l5hacx

Answer 6

this is kind of tedious but first you'd have to find the rate of change between each y value, then on top of that, calculate the rate of change of the rate of change

(this is easier to show through an example so I'll start with the first choice)

Answer 7

-2 --> 24
-1 --> 2
0 --> -1
1 --> 2
2 --> 24

between the y-values, let's calculate the rate of change

going from 24 to 2 is clearly a reduction by 22, so we write -22 as the first change
then from 2 to -1 is a reduction by 3, so -3
repeating this process we get +3 and + 22

Answer 8

now, we put those new changes in a new list, and repeat the process

-22, -3, +3, +22

between -22 and -3 that's an increase of 18
between -3 and 3 that's an increase of 6

since the rate of change is not constant (18 and 6 are different) we can conclude this is not quadratic, so we'd move on to one of the other choices

Answer 9

B is most likely not quadratic just by visual inspection so move on to choice C

Answer 10

LOL okay

Answer 11

try testing choice C using the same process and lmk if you're getting stuck

Answer 12

1 --> -1
2 --> 4
0 --> -4
-1 --> -7
-2 --> -10

from 4 to -1 is 5
from -7 to -4 is -2

Answer 13

hm. i'm getting something weird for choices C and D, let me think about this a little more.

Answer 14

okay

Answer 15

its timed so can we go a little faster loll

Answer 16

is there a way to skip this question

Answer 17

sure we can move on

Answer 18

http://prntscr.com/l5hfb2
http://prntscr.com/l5hfdf

Answer 19

oh that's easy, if a is negative just pick the graph(s) that are opening downward and going to negative infinity

Answer 20

b and a

Answer 21

should be these two

Answer 22

ohh okay

Answer 23

http://prntscr.com/l5hfi4

Answer 24

it's like the pointed part of the graph

Answer 25

i think C

Answer 26

good

Answer 27

http://prntscr.com/l5hfw1

Answer 28

http://prntscr.com/l5hg5t

Answer 29

so you should look for the graph where the pointed part is at (-1,-9) and it crosses the x-axis at 2 and -4

to save some time it's one of the first two choices

Answer 30

A

Answer 31

good

Answer 32

http://prntscr.com/l5hg9r

Answer 33

so the formula of the vertex is -b/2a

since b = -6 and a is 3 you get -(-6)/2(3), so first and third only

Answer 34

got it

Answer 35

http://prntscr.com/l5hgwq

Answer 36

first step is just plugging in x = 3/4 which would be the first one

Answer 37

http://prntscr.com/l5hhs2

Answer 38

length is x, since there are 2 length sides he uses up 2x out of the 100 meters

so the width must be whatever's left, 100 - 2x

area = length * width = x(100-2x)

Answer 39

http://prntscr.com/l5hi27

Answer 40

so basically use -b/2a to find the x-coordinate, then plug it back into the equation to find the y-coordinate

x^2 - 6x + 4, b = -6 and a = 1

so -b/2a = -(-6)/2 = 3, then plug 3 back into x^2 - 6x + 4 to find the y-coordinate and see which table has the result

Answer 41

where do we plug the 3

Answer 42

x = 3, plug this into x^2 - 6x + 4 to get the y-coordinate

Answer 43

y is (0,13)

Answer 44

hm not quite, x = 3 gives us x^2 - 6x + 4 ---> 3^2 - 6(3) + 4 = 9 - 18 + 4 = -5

so (3,-5) making choice B the only viable solution

Answer 45

and do u have a guess for the question we skipped?

Answer 46

B maybe? :S

Answer 47

i was thinking a idk

Answer 48

I tried asking someone else but they haven't replied yet

Answer 49

A might be better idk

Answer 50

A was correct thank you ! LOL