Sorry, misunderstood question, answer beneath me much better.
Check the picture below.
so, the hyperbola looks like so, clearly a = 6 from the traverse axis, and the "c" distance from the center to a focus has to be from -3±c, as aforementioned above, the tell-tale is that part, therefore, we can see that c = 2√(10).
because the hyperbola opens vertically, the fraction with the positive sign will be the one with the "y" in it, like you see it in the picture, so without further adieu,

Answer:
m∠BFE = 171º
BE = 219º
Step-by-step explanation:
∠BFE is supplementary to ∠EFC
m∠BFE = 180 - 9
m∠BFE = 171º
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The angle between two chords is equal to half the sum of the intercepted arcs:
∠BFE = (DC + BE)2
171 = (123 + BE)/2
342 = 123 + BE
219º = BE
The slope is -3/2 and the y-intercept is -3. If you need me to explain I can do that :) hope this helps