Find:

Question

1)x^2-y^2=15, normal at (-8,7)

Answer 1

first, find the slope, then the negative reciprocal of that slope.

2x dx-2ydy=0

Put in x,y and find dy/dx.

Now, the normal will be y=mx+b, m is the negative reciprocal of the dy/dx above, solve for b, and you have it.