to #1):

This is a quadratic in . Use the substitution

Solve for y

Re-substitute to calculate the value(s) of x

to #2)

Let denote the tangent point on the graph of f.

The slope of the tangent is

The equation of the tangent in T is:

This tangent has to pass through P(1, -3) that means the coordinates of P have to satisfy the equation of the tangent:

You get two tangent points and two tangents:

with tangent

with tangent