Graph:
y=abs(-3x)
color(white)(.)color(red)xcolor(white)(..) | color(blue)y=abs(-3x)
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color(red)(-2)color(white)(..)abs(-3*-2)=abs6=color(blue)6
color(red)(-1)color(white)(..)abs(-3*-1)=abs3=color(blue)3
color(white)(..)color(purple)0color(white)(..)abs(-3*0)color(white)(....)=abs0color(white)()=color(purple)0
color(white)(..)color(red)1color(white)(...)abs(-3*1)color(white)(....)=abs(-3)color(white)()=color(blue)3
color(white)(..)color(red)2color(white)(...)abs(-3*2)color(white)(....)=abs(-6)=color(white)()color(blue)6
Plot the points. Draw straight lines through both sets of points, one with -x values, and one with x values.
graph{y=abs(-3x) [-9.96, 10.04, -3.12, 6.88]}
