Your proof is correct and very well done
Answer:

Step-by-step explanation:
Since the foci are at(0,±c) = (0,±63) and vertices (0,±a) = (0,±91), the major axis is the y- axis. So, we have the equation in the form (with center at the origin)
.
We find the co-vertices b from b = ±√(a² - c²) where a = 91 and c = 63
b = ±√(a² - c²)
= ±√(91² - 63²)
= ±√(8281 - 3969)
= ±√4312
= ±14√22
So the equation is

200 is 2 *100 im sorry this is random
The independent variables are the cost for one ticket and the number of student tickets. The cost of the tickets depends on the number of student tickets being purchased. The equation would be c = 7s.