Hi Arturo_026

The line through (-1, 2) : y = mx + c

Subs. (-1, 2) to the equation gives c = 2 + m, so the equation of the line : y = mx + 2 + m

If the line is tanget to the curve, then they will have common point, so :

mx + 2 + m = x^2 + 3x, where m = f '(x) = 2x + 3

Then...