It’s negative by the looks of it.
If you solve it you get -2.5
I hope it’s correct!
Her work is incorrect because she accidentally changed -14 to -7 in the second step.
Working it out from the top we get
(x-14)+11=x-(x-4)
x-14+11=x-x+4
x-3=0+4
Final answer:
x=7
Hope I helped :)
Hi there!

We can calculate slope using the following formula:

Plug in the corresponding points:

Simplify:

Answer:
The hyperbola has two directrices, one for each side of the figure. You can see the hyperbola as two parabolas in one equation. So, as parabolas have directrix, hyperbolas does too.
The directrices are perpendicular to the major axis. That means if the parabolla is horizontal, then its directrices are vertical, and viceversa.
Therefore, to find the right line that forms the directrix of a hyperbola, you just need to use the directrix that is perpendicular to the major axis.