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Find the vertex, focus and directrix of the parabola
`x^(2) + 4x + 2y -7 = 0 ` .

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To find the vertex, focus, and directrix of the parabola given by the equation \( x^2 + 4x + 2y - 7 = 0 \), we will follow these steps: ### Step 1: Rearranging the Equation We start with the equation: \[ x^2 + 4x + 2y - 7 = 0 \] Rearranging it gives: \[ x^2 + 4x = 7 - 2y \] Now we will complete the square for the \( x \) terms. ### Step 2: Completing the Square To complete the square for \( x^2 + 4x \): \[ x^2 + 4x = (x + 2)^2 - 4 \] Substituting this back into the equation gives: \[ (x + 2)^2 - 4 = 7 - 2y \] This simplifies to: \[ (x + 2)^2 = 2y + 11 \] ### Step 3: Rearranging to Standard Form Now, rearranging gives: \[ (x + 2)^2 = 2(y + \frac{11}{2}) \] This is in the standard form of a parabola \( (x - h)^2 = 4p(y - k) \), where \( (h, k) \) is the vertex. ### Step 4: Identifying Vertex From the equation \( (x + 2)^2 = 2(y + \frac{11}{2}) \): - The vertex \( (h, k) \) is \( (-2, -\frac{11}{2}) \). ### Step 5: Finding Focus and Directrix In the standard form \( (x - h)^2 = 4p(y - k) \): - Here, \( 4p = 2 \) implies \( p = \frac{1}{2} \). - The focus is located at \( (h, k + p) = (-2, -\frac{11}{2} + \frac{1}{2}) = (-2, -5) \). - The directrix is given by the line \( y = k - p = -\frac{11}{2} - \frac{1}{2} = -6 \). ### Summary of Results - **Vertex**: \( (-2, -\frac{11}{2}) \) - **Focus**: \( (-2, -5) \) - **Directrix**: \( y = -6 \)
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