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anonymous
 one year ago
am I right at all?
Given that f(x) = 2x + 5 and g(x) = x − 7, solve for f(g(x)) when x = −3.
−15 << my answer
−8
10
25
anonymous
 one year ago
am I right at all? Given that f(x) = 2x + 5 and g(x) = x − 7, solve for f(g(x)) when x = −3. −15 << my answer −8 10 25

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Hero
 one year ago
Best ResponseYou've already chosen the best response.0@FrostFlare23 mind showing the work you did to arrive at that answer?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0alright give me a second

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0well techincally I did work but none of the answers matched mine

Hero
 one year ago
Best ResponseYou've already chosen the best response.0Looks right so far, but ...

Hero
 one year ago
Best ResponseYou've already chosen the best response.0You should calculate f(g(x)) first, then calculate f(g(3)).

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0oh. uhm how do I do that? thats the only thing that confuses me

Hero
 one year ago
Best ResponseYou've already chosen the best response.0I'll get you started: f(x) = 2x + 5 1. Replace x with g(x) f(g(x)) = 2(g(x)) + 5 2. Replace g(x) with x  7 = 2(x  7) + 5 3. Simplify the expression

Hero
 one year ago
Best ResponseYou've already chosen the best response.0So f(g(x)) = 2x  14 + 5, but that can also be further reduced, right?

Hero
 one year ago
Best ResponseYou've already chosen the best response.0Because 14 + 5 = 9 so f(g(x)) = 2x  9 Now calculate f(g(3))

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0hmm. so we would add 14 to both the 5 and the 14?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0oh sorry. lol late comment there

Hero
 one year ago
Best ResponseYou've already chosen the best response.0@FrostFlare23 waiting on you ...

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so we would then divide 2 to both sides to isolate the X in order to get x = 4.5?

Hero
 one year ago
Best ResponseYou've already chosen the best response.0No, you just simply evaluate f(g(x)) at x = 3 f(g(x)) = 2x  9 f(g(3)) = 2(3)  9

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so basically it would become: 2(3) which equals 6. then we subtract 6 from 9 to get 15?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0ok so I was right I just ha the wrong way of doing it the first time thank you!

Hero
 one year ago
Best ResponseYou've already chosen the best response.0Both ways of doing it are correct. It's just better practice to write f(g(x)) as a single expression then evaluate it once.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0alright thank you kind sir!

Hero
 one year ago
Best ResponseYou've already chosen the best response.0The problem with doing it the way is, if someone asked you what f(g(x)) is, you wouldn't be able to tell them.
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