Question 323999
{{{x = 3y}}}
{{{y=(1/3)x}}}
The slope of this line is {{{m=1/3}}}
Perpendicular lines have slopes that are negative reciprocals.
{{{m1*m2=-1}}}
{{{m2=-1/m1=-3}}}
Use the slope-intercept form of  a line {{{y=mx+b}}}
{{{y=-3x+b}}}
Use the point (5,-2/3) to solve for b.
{{{-2/3=-3(5)+b}}}
{{{b=-2/3+45/3}}}
{{{b=43/3}}}
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{{{y=-3x+43/3}}}
{{{3y=-9x+43}}}
{{{highlight(9x+3y=43)}}}
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{{{drawing(300,300,-3,9,-3,9,circle(5,-2/3,.2),grid(1),graph(300,300,-3,9,-3,9,(1/3)x,-3x+43/3))}}}