Question 445955
  <pre><font face = "Tohoma" size = 4 color = "indigo"><b> 
Hi,
the standard slope-intercept form for an equation of a line y = mx + b  
where m is the slope and b the y-intercept.  
 m = -2 and line contains(3,9)
 y = -2x + b
 9 = -2*3 + b
 15 = b 
 y = -2x + 15
{{{drawing(300,300, -20, 20, -20, 20,   grid(1),
circle(3, 9,0.6),
graph(300,300,-20, 20, -20, 20, 0,-2x+15))}}}