Find the equation of the parabola with vertex is at `(2,1)` and the directrix is `x=y-1.`

Explanation

To find the equation of the parabola with a vertex at (2, 1) and a directrix given by the line \( x = y - 1 \), we can follow these steps:

### Step 1: Understand the properties of the parabola
A parabola is defined as the set of points that are equidistant from a point called the focus and a line called the directrix. The vertex is the midpoint between the focus and the directrix.

### Step 2: Identify the vertex and directrix
The vertex is given as \( (2, 1) \). The directrix is given by the equation \( x = y - 1 \), which can be rewritten as \( y = x + 1 \).

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