The equation of the tangent line can be found using slope formula and fact that slope = dy/dx.
\(\frac{dy}{dx} = \frac{y - y_0}{x - x_0}\)
where (x0,y0) is point A ---> (0,-1)
Then rearrange equation into slope-intercept form:
\(y = \frac{dy}{dx}(x - 0) -1\)
Finally sub in x=0 into dy/dx to get slope at the point (0,-1)
\(y = 3x -1\)
