问题471: It is given that the equation of a curve is y + 13 = 15x −

It is given that the equation of a curve is $y + 13 = 15x − x^3$
.A straight line touches the curve at point G such that
x>0. If the straight line is perpendicular to the straight
line $y + 3x − 2 = 0$, find the coordinates of point G.