8
QuizMultiple Choice

Equations of Hyperbolas (continued) — Quiz

Question 8 • Precalculus

What are the foci of the hyperbola whose equation is the fraction with numerator open paren x minus 6 close paren squared and denominator 16 minus the fraction with numerator open paren y plus 7 close paren squared and denominator 9 is equal to 1 ?

Answer
A
open paren 6 comma negative 12 close paren and open paren 6 comma negative 2 close paren
B
open paren 1 comma negative 7 close paren and open paren 11 comma negative 7 close paren
C
open paren 2 comma negative 7 close paren and open paren 10 comma negative 7 close paren
D
open paren 6 comma negative 10 close paren and open paren 6 comma negative 4 close paren

Explanation

The equation is in the form (x − 6)²/16 − (y + 7)²/9 = 1, so the center is (6, −7) and the hyperbola opens left and right. For a hyperbola, c² = a² + b², giving c² = 16 + 9 = 25 and c = 5. The foci are 5 units left and right of the center: (1, −7) and (11, −7), which is choice B.

AI-written and checked against the verified answer.

Previous
Next