help help help please
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Answer:
see explanation
Step-by-step explanation:
To evaluate f(8), substitute x = 8 into f(x) , that is
f(8) = [tex]\sqrt{2(8)+9}[/tex] = [tex]\sqrt{16+9}[/tex] = [tex]\sqrt{25}[/tex] = ± 5
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Equating
[tex]\sqrt{2x+9}[/tex] = 3 ( square both sides )
2x + 9 = 9 ( subtract 9 from both sides )
2x = 0 ⇒ x = 0
Thus
f(0) = 3