I found a similar problem to your problem here, which is shown in the attached picture. So, from the picture, we have to find the equation for the red line. All we have to do is find two points of the line. That would be: Point 1(2,0) and Point 2(-2,3). The general equation would be:
y - y₁ = (y₂-y₁)/(x₂ - x₁) * (x - x₁)
Substituting the coordinates to the equation,
y - 0 = (3-0)/(-2 - 2) * (x - 2)
y = -3(x -2)/4
Rearranging,
4y = -3x + 6 or 4y + 3x = 6
