Question 1085743
A:{{{3x-4y+11=0}}}
B:{{{2x-3y+9=0}}}
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C:{{{y=(-2/3)x+b}}}
C:{{{3y=-2x+3b}}}
C:{{{2x+3y-3b=0}}}

Let the point A be (c,d).
1.{{{3c-4d+11=0}}}
2.{{{2c-3d+9=0}}}
3.{{{2c+3d-3b=0}}}
Add 2 and 3,
{{{2c-3d+9+2c+3d-3b=0}}}
4.{{{4c+9-3b=0}}}
Multiply 1 by 3 and 2 by -4 and add,
{{{9c-12d+33-8c+12d-36=0}}}
{{{c-3=0}}}
{{{c=3}}}
Substituting back into 4,
{{{4(3)+9-3b=0}}}
{{{12+9-3b=0}}}
{{{3b=21}}}
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C:{{{2x+3y-21=0}}}
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*[illustration lp4.JPG].