Find (fog)(x) (gof)(x), if f(x) = 1 - 5x; g (x) = |2x + 3| x

Step-by-step explanation:

f (x) = 1 - 5x

g (x) = 2x + 3

find (fog) (x)

it's a composite function so basically we substitute x = 2x + 3 where we see x in f (x) = 1 - 5x

so doing that we'll get

1 - 5(2x + 3)

next expand your brackets

1 - 10x + 15

equate to 0 to make things easier

1 - 10x + 15 = 0

make x the subject

1 + 15 = 10x (this is the same as 10x = 1 + 15)

x = 16/10 (you can leave it as a fraction)

fog(x) = 16/10

find gof (x)

we'll do the same thing again

2(1-5x) + 3

2 -10x + 3 = 0

2 + 3 = 10x

10x = 5

x = 5/10 (reduce)

x = 1/2

gof (x) = 1/2

the correct answer is $7.38

step-by-step explanation:

$54.99

step-by-step explanation:

$54.99 includes 500 min. if she does not exceed 500 min then her bill is $54.99