Question 1080867
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 perpendicular to the line that contains(5/4,-2) and (3/4,-3)
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Those two points, slope  {{{(-3-(-2))/(3/4-5/4)=-1/(-2/4)=1/(1/2)=2}}}


Slope needed for a perpendicular line will be  {{{-1/2}}}.



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equation of the line that contains the point(2,-4)
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You can start with point-slope form equation.
{{{y-(-4)=-(1/2)(x-2)}}}
and simplify and adjust to slope-intercept form.
{{{y+4=-x/2+1}}}
{{{y=-x/2+1-4}}}
{{{highlight(y=-x/2-3)}}}