Question

Function Notation help please!!

Answer 1

Find f(-7) if f(x) = 2x+8

Answer 2

\[\Large f(\color{#DD4747}{x})\quad=\quad 2(\color{#DD4747}{x})+8\]

Answer 3

\[\Large f(\color{#DD4747}{-7})\quad=\quad 2(\color{#DD4747}{-7})+8\]

Answer 4

Understand how to simplify it from there? :o

Answer 5

I see! So the -7 is the x?

Answer 6

Yah the function is telling us to plug in -7 for every x in the equation.

Answer 7

Thank you!

Answer 8

I don't wanna sound like one of those kids who just want the answer, but I'm really having trouble with this concept. can you take me through the rest of the question?

Answer 9

The function is telling us to plug -7 in for our x, so we do that:
\[\Large f(\color{#DD4747}{-7})\quad=\quad 2(\color{#DD4747}{-7})+8\]
To simplify the right side down, hmm
I guess we'll start by multiplying the -7 and 2.

Answer 10

Okay

Answer 11

What's -7*2 = ?
:D

Answer 12

-14 lol

Answer 13

Ok good good,\[\Large f(\color{#DD4747}{-7})\quad=\quad -14+8\]

Answer 14

To finish up the problem, we add.

Answer 15

-14+8=-6 lol

Answer 16

\[\Large f(\color{#DD4747}{-7})\quad=\quad -6\]
Mmm ok good good :)
So there are a few ways to interpret this.

Answer 17

When we `input` -7 into the function,
the `output` is giving us -6.

We put x=-7,
f(x) gives us -6 for that particular x value.

Answer 18

Function notation can be tricky D: takes a little getting used to.

Answer 19

That really helped me understand it!!!! THANK YOU SO MUCH!!!!!!!

Answer 20

\c:/ np!

Answer 21

I would give you 100000 badges if I could lol!
:D