Answer:
(y+7)²/364 - (x+8)²/364 = 1
Explanation:
This is the standard form of a vertical hyperbola (y-k)²/a² - (x-h)²/b² = 1
so, (y²+14y+?) - (x²+16x+?) = 251
(y²+14+49)-49 - (x²+16x+64)-64 = 251
(y+7)² - (x+8)² = 251 + 49 + 64
(y+7)² - (x+8)² = 364
(y+7)²/364 - (x+8)²/364 = 1