Given $g (x) = 5 x^{2} - 4 x$ $g(x) = 5x^2 - 4x$ and $h (x) = 3 x + 9$ $h(x) = 3x + 9$ how do you find g(h(x))?

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Given $g (x) = 5 x^{2} - 4 x$ $g(x) = 5x^2 - 4x$ and $h (x) = 3 x + 9$ $h(x) = 3x + 9$ how do you find g(h(x))?

2 Answers

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Answer 1 · 2016-02-03T22:11:02

This means that you must plug in h into g

Explanation:

g(h(x)) = g(3x + 9)

= $5 {(3 x + 9)}^{2} - 4 (3 x + 9)$ $5(3x + 9)^2 - 4(3x + 9)$

= $5 (9 x^{2} + 54 x + 81) - 12 x - 36$ $5(9x^2 + 54x + 81 ) - 12x - 36$

= $45 x^{2} + 270 x + 405 - 12 x - 36$ $45x^2 + 270x + 405 - 12x - 36$

= $45 x^{2} + 258 x + 369$ $45x^2 + 258x + 369$

Hopefully this helps!

Answer 2 · 2016-02-03T22:24:24

$g (h (x)) = 45 x^{2} + 258 x + 369$ $g(h(x))=45x^2+258x+369$

Explanation:

$g (x) = 5 x^{2} - 4 x$ $g(x)=5x^2−4x$ , $h (x) = 3 x + 9$ $h(x)=3x+9$
$g (h (x)) = g (3 x + 9)$ $g(h(x))=g(3x+9)$
$= 5 {(3 x + 9)}^{2} - 4 (3 x + 9)$ $=5(3x+9)^2-4(3x+9)$
$= 5 (9 x^{2} + 54 x + 81) - 12 x - 36$ $=5(9x^2+54x+81)-12x-36$
$= 45 x^{2} + 270 x + 405 - 12 x - 36$ $=45x^2+270x+405-12x-36$
$= 45 x^{2} + 258 x + 369$ $=45x^2+258x+369$ => expanded form

$3 (15 x^{2} + 86 x + 123)$ $3(15x^2 + 86x + 123)$
$= 3 (15 x + 41) (x + 3)$ $=3(15x+41)(x+3)$ => factored form

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Given $g (x) = 5 x^{2} - 4 x$ $g(x) = 5x^2 - 4x$ and $h (x) = 3 x + 9$ $h(x) = 3x + 9$ how do you find g(h(x))?

2 Answers

Explanation:

Explanation:

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Given g(x) = 5x^2 - 4xg(x)=5x2−4xg(x) = 5x^2 - 4x and h(x) = 3x + 9h(x)=3x+9h(x) = 3x + 9 how do you find g(h(x))?

2 Answers

Explanation:

Explanation:

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Given $g (x) = 5 x^{2} - 4 x$ $g(x) = 5x^2 - 4x$ and $h (x) = 3 x + 9$ $h(x) = 3x + 9$ how do you find g(h(x))?