Question

Which relation is a function?

A. {(1, 2); (1, 3); (3, 2); (4, 2)}
B. {(1, 2); (2, 5); (3, 2); (4, 5)}
C. {(1, 2); (2, 3); (3, 4); (2, 5)}
D. {(1, 2); (2, 3); (3, 4); (1, 5)}

B?

Answer 1

Functions are for each value of x (the first number in an ordered pair) there can only be one y value (the second number in an ordered pair).

Answer 2

a function will have NO X-REPEATS

Answer 3

Yeah, so B is correct

Answer 4

Thanks! I cant afford to get any wrong!
Hi @math&ing001

Answer 5

How come I can't tag your name?

Answer 6

Hey there :)

Answer 7

Sorry.. computer glitching..
how are you?
Do you think you can help me with other questions? I don't want to get any wrong!

Answer 8

@math&ing001 ?

Answer 9

Yeah, sure

Answer 10

Thanks!

For the function f(x) = 2 – 3x, find f(0).

A. 2
B. 5
C. –1
D. –3

Its a bit confusing.. but I don't think the answer is positive?

Answer 11

You just replace the x with 0 like this:
f(0) = 2 - 3*0

Answer 12

Oh.. then its A? -.- Wow..

Answer 13

Yep ^^

Answer 14

Thanks! :)

Which is the equation of the function graphed?

A. f(x) = |x| – 4
B. f(x) = |x – 4|
C. f(x) = |x| + 4
D. f(x) = |x + 4|

Answer 15

Can you try to figure it out ? Plug in some values in your functions and see which one corresponds to the graph given.

Answer 16

Umm.. I'm not soo good at graphs.. would it be x + 4.. I'm not sure where the lines go

Answer 17

Do you know what this sign means |x| ?

Answer 18

Ya.. but I don't know how to explain.. like when |-9| its 9.. right?

Answer 19

Yeah it's the absolute value of x meaning the non-negative value of x.
For exemple f(-2)=|-2|+4=2+4=6

Answer 20

I see.. would it be D..?

Answer 21

Nope, but how did you get it ?

Answer 22

I'm still confused.. and I don't know :/ but the answer is x + 4 which is either C or D?

Answer 23

Ok plug in 0 for both choices and see what it gives you

Answer 24

You mean for f(x)?

Answer 25

yep

Answer 26

Umm.. give me a minute

Answer 27

My head hurts.. can you explain more, please?

Answer 28

I'm gonna do the first one, you do the second one.
D - f(0) = | 0 + 4 | = |4| = 4

Answer 29

f(0) = |0| + 4 = 4
same answer..? :/

Answer 30

Yeah, correct !And they both belong to the graph. So we try another point say -4. Let's see what we get now.

Answer 31

You mean -4 for x?

Answer 32

Exactly

Answer 33

for C - |-4| + 4 = 4 + 4 = 8
for D - |-4 + 4| = |0| = 0
correct?

Answer 34

Yeah ! So which function is graphed

Answer 35

C...?

Answer 36

Yep !

Answer 37

Yes, finally! thanks :) more graphs up ahead.. >,<

Answer 38

Which is the graph of the function g(x) = –|x + 3|?

Answer 39

what are we supposed to replace for x?

Answer 40

You can choose any value you want. Always start easy like 0 for example and narrow down your choices.

Answer 41

ok, so from 0 and go down, negatives?

Answer 42

can you give me one example?

Answer 43

It doesn't matter, those are just random value that help you identify your graph.
Example: g(1)= - | 1+3 | = -4
Only graph 3 checks, so graph 3 is the one we're looking for.

Answer 44

I see... I'm sorry, but I just not good at graphs :(

Answer 45

Which equation represents a direct linear variation?
A. y = 1/2x
B. y = x + 2
C. 1/x
D. y = x^2

B?

Answer 46

No worries :)

Answer 47

I gotta go sleep it's 12 am already :p

Answer 48

Oh, ok, bye then! You know anyone else who can help me, like you do?

Answer 49

There's @hartnn but I'm not sure he's online atm

Answer 50

Oh, ok.. can you answer the last question above? I said it was B :P

Answer 51

Yep, that's correct !

Answer 52

Ok, thanks! I don't know anyone on who will help me like you do :P Bummer..

Answer 53

I know a bunch but they're not online right now, well good night :)

Answer 54

Ok.. bye!