Answer:
Explanation:
The general formula for a horizontal hyperbola :
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Given: a = 1 we know a² = 1 ,and that c = 9 so we know c² = 9² = 81
We also know that the relation between a, b, c for a hyperbola is c²= a²+b²
c²= a²+b², substitute what we know
81 = 1 +b², subtract 1 from both sides of the equation
80 = b²
The equation of our hyperbola is:
or
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