Question

What is the axis of symmetry for the graph of y = 4x2 + 16x + 10?

x = 4

x = −4

x = −2

x = 2

Question 2 (Multiple Choice Worth 1 points)

[9.03] What is the domain of the graph of y = −x2 + 6x + 11?

x ≤ 3

All real numbers

x ≤ −3

x ≥ 3

Answer 1

You are looking for the center line of the parabola... x=-b/(2a)=-16/(2x4).

Answer 2

can u help me :(

Answer 3

And all quadratic functions have a domain from negative infinity to positive infinity.

Answer 4

so for the first answer i got -2 im i right

Answer 5

Yes.

Answer 6

yeahhhh thanks WAT about the 2 question

Answer 7

Look up to my second reply.

Answer 8

x ≤ −3

Answer 9

did i get it right

Answer 10

I'm trying to use some math lingo so that I am not just spitting out the answer. It is not x<=-3

Answer 11

ohh its x ≤ 3

Answer 12

nope

Answer 13

from negative infinity to positive infinity

Answer 14

x ≥ 3 or all real numbers i think its x ≥ 3 thats what i got

Answer 15

Domain asks the question, which numbers that I put in will give me an answer that exists? (or all possible x values) There is nothing that will cause a problem with this (no divide by zeros or negative square roots) so any thing will work.

Answer 16

ok thanks so its all real numbers

Answer 17

yes :)

Answer 18

Which equation below has an axis of symmetry of x = 4 over 3?

y = −3x2 − 4x + 5

y = −3x2 + 4x + 5

y = −3x2 − 8x − 1

y = −3x2 + 8x − 1

Question 6 (Multiple Choice Worth 1 points)

[9.03] What is the range of the graph of y = −3x2 − 12x + 5?

All real numbers

y ≤ −2

y ≥ 17

y ≤ 17

Answer 19

For the first one.
You need to check -b/(2a) for each until you find 4/3 as your answer.

Answer 20

For the second one:
Range is all of the possible y values. It takes a bit more analysis than domain.
First find where the vertex will occur (x value) using -b/(2a). I get -2.
Then put that number back into the function as x to find the y... that is where the parabola starts (I get -3(-2)(-2)-12(-2)+5=17).
Then see if it is right side up or upside down. This one is opening downward because of the minus sign in front... so for y-values (range), it starts at 17 and goes down.

Answer 21

thanks