Question

Given that f(x) = −x + 4 and g(x) = −2x − 3, solve for f(g(x)) when x = 2.

1. -14
2.-7
3.7
4.11

Answer 1

first step is to solve g(x) when x = 2
then take the result and plug it into f(x)

Answer 2

Do I divide 2 to -2x and -3?

@Vocaloid

Answer 3

... huh?
let's take it one step at a time:

what is g(x) when x = 2?

Answer 4

okay so g(2)=-2x-3 what do I do next with this funtion? @Vocaloid

Answer 5

plug in 2 for x and tell me what you get when you solve it

Answer 6

I'm a bit unsure if it's right but negative 7

Answer 7

yup! g(2) = -7

alright, so now let's plug in -7 for x using f(x)

Answer 8

f(-7)=-4(-7)=9 I'm I wrong at some part?
@Vocaloid

Answer 9

uh, not quite

f(x) = -x+4, remember?

Answer 10

if x = -7, what is f(x)?

Answer 11

oh that was my fault I plugged it in for the wrong problem @Vocaloid

Answer 12

instead of the x it would be F(-7) Am I right? @Vocaloid

Answer 13

yup, so what is our answer? :)

Answer 14

F(-7)=-7+4
F(-7)=-3
what am I going to use F(-7) for? @Vocaloid

Answer 15

not quite, check your math again

f(-7) = -(-7) + 4 = ?

Answer 16

F(-7)=-7+4
F(-7)=-3
F(g(2))=-7 right? :) @vocaloid

Answer 17

uh... not quite...

what is -(-7)?

Answer 18

hint: -(-a) = a

Answer 19

the answer for g(x) function

Answer 20

no, can you please answer my question?

-(-7) = ?
hint: -(-a) = a

Answer 21

I do not know

Answer 22

I'm a bit slow right now sorry

Answer 23

well, ok, we know that f(-7) = -(-7) + 4, right?
-(-7) = 7, so f(x) = 7 + 4 = 11

11 is our answer

Answer 24

full explanation:

the question asked for f(g(x)) when x = 2
that means, plug in 2 for x to find g(2)
g(2) = -7, so we plug in -7 for x in f(x)
f(-7) = 11, meaning f(g(2)) = 11

Answer 25

but how did you get that negative in front of the perentheses

Answer 26

f(x) = -x+4
x = -7
f(x) = -(-7) + 4

Answer 27

oh so the negative of the other x was still be in play

Answer 28

yup!

Answer 29

that's what i was missing hahah:) i might be a dumbarse but thanks a lot you're a really good helper :)

Answer 30

@Vocaloid