Question

Given the following functions f(x) and g(x), solve f[g(7)] and select the correct answer below:

f(x) = 4x + 21

g(x) = 2x + 2

16
49
85
784

Answer 1

g(7) = 2(7) + 2 = 16

Answer 2

oops - my bad thinking
now you need to plug x = 16 into f(x)

Answer 3

4(16) + 21 = ?

Answer 4

- this gives you the value of f[g(7)]

Answer 5

85

Answer 6

so C

Answer 7

yes

Answer 8

can you help with another ?

Answer 9

one more

Answer 10

Given the functions f(x) = 7x + 13 and g(x) = x + 2, which of the following functions represents f[g(x)] correctly?

f[g(x)] = 7x + 15
f[g(x)] = 7x + 27
f[g(x)] = 7x2 + 15
f[g(x)] = 7x2 + 27

Answer 11

you need to replace the x in f(x) - that is 7x + 13 - by g(x) which is x + 2 then simplify

so we get

7(x + 2) + 13

- can you simplify this further?

Answer 12

yes but how ?

Answer 13

7(x + 2) + 13
= 7*x + 7*2 + 13
= ?

Answer 14

you distribute the 7 over the x + 2

Answer 15

- that was the first step

Answer 16

so now its just simplifying
7x + 7*2 + 13

Answer 17

is it A ?

Answer 18

no
what is 7*2 ?

Answer 19

7 times 2

Answer 20

surely you know what 7 times 2 is?

Answer 21

right so we have
7x + 14 + 13
- now is just one add and you have the answer

Answer 22

add the 2 numbers

Answer 23

correct 7x + 27

Answer 24

thanks

Answer 25

yw