Question 895406
{{{graph(200,200,-5,12,-5,12,abs(8-x))}}}


A critical point is at x=8; and because the function itself is an absolute value, f has no points below the x-axis.


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{{{8-x>=0}}} for {{{highlight_green(x<=8)}}}.
{{{f(x)=abs(8-x)=8-x}}}
{{{highlight(f(x)=8-x)}}} for {{{highlight(x<=8)}}}.


{{{8-x<0}}} for {{{8<x}}} or {{{highlight_green(x>8)}}}.
{{{f(x)=abs(8-x)=-(8-x)=x-8}}}
{{{highlight(f(x)=x-8)}}} for {{{highlight(x>8)}}}.


Additional note to help understanding:  An absolute value is always positive or zero; NEVER negative.