When I put this into y2-y1/x2-x1 (equation to find slope) I did the coordinate pairs (3,-9) and (4,-11). When you plug it in it’s -11+9/4-3. This gets you -2/1, which is -2. That’s your slope. Then, in order to get the y-intercept, you can use any of those pairs. I did -9 = 3(-2) + b. -9=-6 + b and in the end this gets you -3 = b. So the full equation is y = -2x - 3.
Find the Equation of a Line Given That You Know a Point on the Line And Its Slope. The equation of a line is typically written as y=mx+b where m is the slope and b is the y-intercept.
