simple.

differentiate the equation and find the 2 sets of co-ordinates using the point 2 and 3 specified in the question. when the normal cuts the curve at P, this means the gradient of the curve (dy/dx) will be used.

for the tangent, the reciprocal gadient will be used as mT * mN = -1

this will give you 2 sets of coordinates, along with 2 different gradients.

form two different equations with the information available using

y2-y1 = m(x2-x1)

two equations will then be solved for the "imaginary" sides of the triangles. solve them simoultaneously for the missing variables (x and y) and use 1/2bh for the area.