MHB Function given, find values of x if...

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To find the values of x for the function f(x)=3√(x+4) given that f(x)≥4, one must first set up the inequality 3√(x+4)≥4. This simplifies to √(x+4)≥4/3, leading to x+4≥(16/9) when both sides are squared. By solving the resulting equation, x must be greater than or equal to (16/9) - 4, which is approximately -1.56. The constraints x≥-4 and y≥0 are satisfied within this range, confirming the solution is valid. Thus, the values of x that meet the criteria can be determined through these calculations.
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f(x)=3\sqrt{x+4} & x\ge-4;y\ge0

then if f(x)\ge4 find the values of x

Do I then ignore x\ge-4;y\ge0 and replace f(x) with 4 ?

How would I go about solving this?
 
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Hint: start with $$x+4=\dfrac{16}{9}$$

*Note: for LaTeX to render correctly here enclose your code in [math]...[/math] tags.
You may also use $$...$$. Use $...$ for inline code.
 
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