What is the graph of the function f(x) =-x^2+x+20/x+4
Start by factoring the top and bottom.
how do i do that?
it is a line. Factor the top.
Let me give you an example : x^2 +6x +4 This factors to (x+4)(x+2)
x+4 cancel on top and bottom
\(\bf -x^2+x+20\implies -(x^2-x-20)\)
thus factor the numerator.... and \(\bf f(x)=\cfrac{(\qquad )\cancel{ (\qquad ) }}{\cancel{ x+4 }}\)
-(+4)(x-5)?
-[ (x+4)(x-5) ] is correct so \(\bf f(x)=\cfrac{-[\cancel{ ( x+4) }(x-5 )]}{\cancel{ x+4 }}\)
so that'd be the graph of that is a line, pick a couple of random "x" and get a "y" plot the line :) keeping in mind the "restrictions" of the original rational that when the denominator is 0, the fraction becomes "undefined" and thus has a hole there due to discontinuity \(\bf f(x)=\cfrac{-x^2+x+20}{{\color{brown}{ x+4}}}\qquad {\color{brown}{ x+4}}=0\qquad \cfrac{-x^2+x+20}{{\color{brown}{ 0}}}\to discontinuous\)
hmm actually..... it may not be discontinuous
\(\huge\color{ blue }{\huge {\bbox[5pt, cyan ,border:2px solid white ]{ \LARGE\text{Chart for f(x) .}\\ \begin{array}{|c|c|c|c|} \hline~~~~~~\textbf{x}~~~~~~ ~&~~~~~~\textbf{f(x) }~~~~~~\\ \hline\text{0} &\text{4} \\ \text{1} &\text{5} \\ \text{2} &\text{6} \\ \text{3} &\text{7} \\ \text{4} &\text{8} \\ \text{••••} &\text{••••} \\ \hline \end{array} }}}\)
well, jdoe, it is just f(x)=x+4 , technically.
yeah.... when the denominator zeros out, so does the numerator....so it wouldn't be discontinous
none of the graphs that are answers are just like a straight line... im confused
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