A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 3 years ago
Is y=x^2+4 a function? How do you know?
anonymous
 3 years ago
Is y=x^2+4 a function? How do you know?

This Question is Closed

abb0t
 3 years ago
Best ResponseYou've already chosen the best response.1Of course it's a function!

abb0t
 3 years ago
Best ResponseYou've already chosen the best response.1If it passes the vertical line test, it's a function.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0I checked the answer key, and it's not a function..

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1Have you checked the definition of a "function"?

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1What does does it say?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0A function is a special relationship between values: Each of its input values gives back exactly one output value.

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1Set up a table of values like ...3, 2, 1, 0, 1, 2, 3, .. and test it.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0How does that let me know whether it's a function or not?

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0lol, it's just a question

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1Does each input value give "back exactly one output value."???

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Oh, I understand now! Thanks :)

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0But, won't I have to try out all of the numbers? What if somewhere along the line, the x has more than one y value?

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.1are you sure you haven't entered the equation incorrectly perhaps it should be \[x= y^2 + 4\]

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0No, that is incorrect. The y value is always the output.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0omg it's just a correctionnn

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.1no its a graph that looks like dw:1359706698575:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Well, that's the reflection of y=x^2+4 over the y axis, but no that's not correct. I have the answer key

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1Once you try a few input values you will be able to draw a "graph" like above...

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Wait @campbell_st how did you get that graph?

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.1It the graph of \[x = y^2 + 4\] which isn't a function and that's why I asked if you had typed in the correct equation. Because the equation you have entered for the question is definitely a function...

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Oh yes! Yes, that is what I meant. I have a question for you!

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1Once you try a few input values you will be able to draw a "graph" of the output values.

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0how do you get function for this line? dw:1359707035624:dw

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0*how do you get the function for this line

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Like, how did you know it was x=y^2+4?

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.1yep... so as @abb0t said... if you use a vertical line you can see it cuts the curve twice... so its not a function... if the vertical like only cuts once you have a function...

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0For all we know, couldn't it have been y=(x+4)^2

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.1because you said that the answer was... not a function.. which to me you have transposed the x and y.... just an experience thing

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0The vertical line test made it so much easier! So @abb0t was correct in the first place :P

campbell_st
 3 years ago
Best ResponseYou've already chosen the best response.1and any parabola with x as the independent variable will be a function..

anonymous
 3 years ago
Best ResponseYou've already chosen the best response.0Thank you :) You made it clear for me

skullpatrol
 3 years ago
Best ResponseYou've already chosen the best response.1Or the answer key is wrong...the important thing is to know to use the definition: A function is a special relationship between values: Each of its input values gives back exactly one output value.
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.