m=0 and the y-intercept is (0,-2)
y - y₁ = m(x - x₁)y - (-2) = 0(x - 0) y + 2 = 0(x) - 0(0) y + 2 = 0(x) + 0(0) y + 2 = 0x + 0 - 2 - 2 y = 0x - 2 y = -2