## anonymous one year ago Let f(x) = -4x + 7 and g(x) = 10x - 6. Find f(g(x)).

1. Nnesha

$\huge\rm f(\color{red}{g(x)})\textrm {is same as }f(\color{reD}{10x-6})$ so substitute x for 10x-6 into f(x) function

2. anonymous

so it would be x = 3/5?

3. Nnesha

no f(g(x)) means you should substitute x for g(x) function which is 10x-6 so in other words replace x by 10x-6 x=10x-6

4. anonymous

ohh okay

5. Nnesha

$\huge\rm f(\color{reD}{10x-6})=-4\color{reD}{x}+7$ replace the x by 10x-6

6. anonymous

wait i'm still confused

7. Nnesha

okay say it:=)

8. Nnesha

so what's ur question ?

9. anonymous

i don't get what you do after replacing the x with 10x-6

10. Nnesha

ohh distribute parentheses by 6

11. Nnesha

$\huge\rm f(\color{reD}{10x-6})=-4\color{reD}{(10x-6)}+7$ distribute parentheses by 4 and then combine like terms

12. anonymous

so then f = -4(20x - 12) + 7 ??

13. Nnesha

hmm no

14. Nnesha

multiply both terms in the parentheses by outside number $\huge\rm a(b+c)=a \times b+a \times c$ like this

15. Nnesha

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16. anonymous

OHH so it's -40x + 24

17. Nnesha

$\huge\rm \color{reD}{-4(10x-6)}+7$ $\huge\rm \color{reD}{-40x+24}+7$ red part equal to -4x+24 right now combine like terms