The equation of the directrix of a hyperbola is `x-y+3=0.` Its focus is (-1,1) and eccentricity 3. Find the equation of the hyperbola.

Explanation

To find the equation of the hyperbola given the directrix, focus, and eccentricity, we can follow these steps:

### Step 1: Identify the given information
- The equation of the directrix is: \( x - y + 3 = 0 \)
- The focus is: \( (-1, 1) \)
- The eccentricity \( e = 3 \)

### Step 2: Rewrite the directrix equation in standard form
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