Given $f(x) = 4x + 5$ and $h(x) = sqrt(5x - 4)$ how do you find (hf)(4)?

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Answer 1 · 2018-07-27T11:16:47

$( hf)(4) =sqrt 101$

$f(x)= 4 x+5 , h(x)= sqrt (5 x-4)$

$(hf)(x)=h(f(x)) = h ( 4 x +5) = sqrt ( 5(4 x+5)-4)$

$(hf)(4) = sqrt ( 5(4*4+5)-4) = sqrt (105-4) =sqrt 101$

$:.( hf)(4) =sqrt 101$ [Ans]

Given f(x) = 4x + 5f(x) = 4x + 5 and h(x) = sqrt(5x - 4)h(x) = sqrt(5x - 4) how do you find (hf)(4)?