When will the dependent variable in the equation y = sqrtx+4 -3 equal or exceed 4?

Question

cloverracer · Answer

@Hero @mathmale @satellite73

cloverracer · Answer

I know you have to plot this in a table but I don't know how to

mathmale · Answer

y is the "dependent variable" in  your equation  y = sqrtx+4 -3.  x is the "independent variable."

this problem statement asks when the dependent variable will equal or exceed 4.  Equivalently, $$y \ge4$$

mathmale · Answer

Sorry, but I realize I do not know what you mean when you type y = sqrtx+4 -3.  Please re-type that, with parentheses, so that I can know the argument (input) to the Sqrt function without any ambiguity.  Or, better yet, present your equation using Equation Editor (below).

cloverracer · Answer

$$y = \sqrt{x+4} - 3$$

mathmale · Answer

Yes.  That's SO much better.  Now this problem states that the "dependent variable" is = to or greater than 4.   Take your equation, immediately above, and write the necessary inequality.

cloverracer · Answer

$$0 \ge4$$

cloverracer · Answer

$$y \ge 4$$ sorry

mathmale · Answer

$$y \ge4$$is correct, but I'd asked you to substitute your expression (your function in x) for y.  Try again.  Write the inequality.

cloverracer · Answer

my function for x can be any number right?

mathmale · Answer

Yes, substitute your expression involving the square root of (x+4) for y in the inequatlity you've just written.

cloverracer · Answer

I don't quite understand.

cloverracer · Answer

for (x+4) do I put (2+4)?

mathmale · Answer

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