Question 387847
  <pre><font size = 3 color = "indigo"><b>
Hi
Using the point-slope formula, {{{m =(y[2] - y[1])/(x[2] - x[1])}}}
  (1, -9) and (3, -1). 
 m = -1 -(-9)  / 3-1  = 8/2 = 4
 m = 4
Using the standard slope-intercept form for an equation of a line y = mx + b  where m is the slope and b the y-intercept.  
 y = 4x + b using ordered pair pt(3,-1) to solve for b
 -1 = 4*3 + b
 -13 = b
 y = 4x - 13
{{{drawing(300,300, -15, 15, -15, 15,  grid(1),
circle(1, -9,0.5),
circle(3, -1,0.5),
circle(0, -13,0.5),
graph( 300, 300,  -15, 15, -15, 15, 4x - 13
))}}}