Question

f(x) = 4x + 5
g(x) = 7x - 2
Find: (f - g)(7)

Answer 1

Same thing! See what happens if you substitute 7 in for x for both equations

Answer 2

would i muiltiply by 7 at the end or no?

Answer 3

nope

Answer 4

just subtract what you get for both functions are putting 7 in

Answer 5

thanks (:

Answer 6

-are +after

Answer 7

what?

Answer 8

i said are instead of ater

Answer 9

after*

Answer 10

whyy?

Answer 11

can you help me out with this one @blurbendy
f(x) = 4x + 5
h(x) = √5x - 4
Find: (hf)(4)

Answer 12

substitute 4 in for x for both equations then multiply

is for h(x) is everything under the square root symbol or just 5x?

Answer 13

everything.

Answer 14

thats what i did but i didnt get any of the choice

Answer 15

sqrt[5(4) -4) = sqrt[16] = 4

f(4) = 4(4) + 5 = 21

21*4 = 84

Answer 16

thanks (:

Answer 17

ur welcome

Answer 18

im confused on this one, what do i substitiute? .

f(x) = 2x - 7
g(x) = -4x2 - 6x
Find: g(f(x))

Answer 19

so now we have to put f(x) into g(x)

so, wherever you see an x in g(x), put f(x) in there

g(2x-7) = -4(2x-7)^2 - 6(2x-7)

(2x-7)^2 = (2x -7)(2x-7) = 4x^2 -14x - 14x + 49 = 4x^2 -28x + 49

-4 ( 4x^2 - 28x +49) = -16x^2 + 112x - 196 - 6(2x - 7)

= -16x^2 + 112x - 196 - 12x + 42

= -16x^2 + 100x -154

Answer 20

thank youuu (:

Answer 21

yw

Answer 22

would this be the same? g(x) = 5x^2 - 4x
h(x) = 3x + 9
Find: g(h(x))

Answer 23

@blurbendy

Answer 24

hey i had to grab a snack. yes, the same idea applies