Question 170567
we know that perpendicular lines have  slopes that are negative  reciprocals of each other....so lets find the slope of our given equation by writing it in y=mx+b format where m is the slope.
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3x-4y=9--->4y=3x-9---->y=3x/4-9/4...therefore the slope is 3/4.....the slope of any line perpendicular to this line would have a slope of -4/3.  
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we now have the slope -4/3 and a point (-2,-1).  Using the point slope formula we have   y+1=-4/3(x+2)---->lets distribute and write this in standard form
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y+1=-4/3x-8/3---->multiply all terms by 3
:
3y+3=-4x-8 add 4x and subtract -3 from both sides
:
{{{highlight(4x+3y=-11)}}}