The line is perpendicular to the line from origin to P (by tangent is perpendicular to radii)
Which slope is 1/4
So the
(slope of tangent) x (1/4) = -1
Slope of tangent = -4
Point slope form:
(y-1)/(x-4)=-4
y-1=-4x+16
y=-4x+17
Or you can construct the upper half of the circle in y=(17-x^2)^(1/2) and differentiate it to get the slope then use point slope form again
