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Find vertex, focus, directrix and latus rectum of the parabola `y^(2)+4x+4y-3=0`.

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To find the vertex, focus, directrix, and latus rectum of the parabola given by the equation \( y^2 + 4x + 4y - 3 = 0 \), we will follow these steps: ### Step 1: Rearranging the equation Start by rearranging the equation to isolate the \( y^2 \) term: \[ y^2 + 4y = -4x + 3 \] ### Step 2: Completing the square Next, we complete the square for the \( y \) terms: \[ y^2 + 4y + 4 = -4x + 3 + 4 \] This simplifies to: \[ (y + 2)^2 = -4x + 7 \] or \[ (y + 2)^2 = -4(x - \frac{7}{4}) \] ### Step 3: Identifying the vertex From the equation \( (y - k)^2 = 4p(x - h) \), we can identify the vertex \((h, k)\): - Here, \( h = \frac{7}{4} \) and \( k = -2 \). - Thus, the vertex is: \[ \text{Vertex} = \left( \frac{7}{4}, -2 \right) \] ### Step 4: Finding the focus The value of \( p \) (the distance from the vertex to the focus) is given by \( p = -1 \) (since \( 4p = -4 \)). The focus is located at: \[ \text{Focus} = \left( h + p, k \right) = \left( \frac{7}{4} - 1, -2 \right) = \left( \frac{3}{4}, -2 \right) \] ### Step 5: Finding the directrix The directrix is a vertical line given by: \[ x = h - p = \frac{7}{4} + 1 = \frac{11}{4} \] ### Step 6: Finding the latus rectum The length of the latus rectum is given by \( |4p| \): \[ \text{Length of Latus Rectum} = |4 \cdot (-1)| = 4 \] The endpoints of the latus rectum can be found by moving \( 2 \) units up and down from the focus: \[ \text{Endpoints} = \left( \frac{3}{4}, -2 + 2 \right) \text{ and } \left( \frac{3}{4}, -2 - 2 \right) = \left( \frac{3}{4}, 0 \right) \text{ and } \left( \frac{3}{4}, -4 \right) \] ### Summary of Results - **Vertex**: \( \left( \frac{7}{4}, -2 \right) \) - **Focus**: \( \left( \frac{3}{4}, -2 \right) \) - **Directrix**: \( x = \frac{11}{4} \) - **Length of Latus Rectum**: \( 4 \) (Endpoints: \( \left( \frac{3}{4}, 0 \right) \) and \( \left( \frac{3}{4}, -4 \right) \))
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