Question 305436
Parallel lines have identical slopes, they maintain the relationship between x and y as the original equation.
{{{3x+y=7}}}
Keep the left hand side, solve for the right hand side using the point.
{{{3x+y=3(-2)+(-9)=-6-9=-15}}}
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{{{3x+y=-15}}}
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{{{ drawing(300,300,-10,10,-10,10,grid(1),circle(-2,-9,.35),graph( 300, 300, -10, 10, -10, 10, 7-3x, -15-3x)) }}}