Find the y-intercept (b) of the ordered pairs (-2,8) (0,0) (1,-4) (3,-12) (5,-20)
+37146 We don't need ALL of these ordered pairs to get the slope....
let's just use the first two
y=mx+b is the equation of a line where m= slope and b = y-intercept
slope = m = (y2-y1)/(x2-x1) = (0-8)/(0-(-2)) = -4 slope
y=mx+b reults in y = -4x + b if we sub in a point (-2,8) we will find b=0 which is the y-intercept
so your equation of the line becomes just y= - 4x You can substitute in the other ordered pairs to see if they 'fit' (they do)
D'oh! I just looked at this again.....one of the ordered pairs is 0,0 <------ obviously this is the y-intercept ! (AND the x-intercept)...... Sorry for making this more complicated than it needed to be....
