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Find the coordinates of the centre , foc...

Find the coordinates of the centre , foci, and ends points of latus rectum of the hyperbola `9x^(2)-16y^(2)+18x-64y-199=0` . Also find the length of axes.

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To find the coordinates of the center, foci, endpoints of the latus rectum, and the lengths of the axes of the hyperbola given by the equation \(9x^2 - 16y^2 + 18x - 64y - 199 = 0\), we will follow these steps: ### Step 1: Rearranging the Equation Start by rearranging the equation into a standard form. Given: \[ 9x^2 - 16y^2 + 18x - 64y - 199 = 0 \] Rearranging gives: \[ 9x^2 + 18x - 16y^2 - 64y = 199 \] ### Step 2: Completing the Square Next, we will complete the square for the \(x\) and \(y\) terms. For \(x\): \[ 9(x^2 + 2x) = 9((x + 1)^2 - 1) = 9(x + 1)^2 - 9 \] For \(y\): \[ -16(y^2 + 4y) = -16((y + 2)^2 - 4) = -16(y + 2)^2 + 64 \] Substituting these back into the equation: \[ 9(x + 1)^2 - 9 - 16(y + 2)^2 + 64 = 199 \] \[ 9(x + 1)^2 - 16(y + 2)^2 + 55 = 199 \] \[ 9(x + 1)^2 - 16(y + 2)^2 = 144 \] ### Step 3: Dividing by 144 Now, divide the entire equation by 144 to get it into standard form: \[ \frac{(x + 1)^2}{16} - \frac{(y + 2)^2}{9} = 1 \] ### Step 4: Identifying Parameters From the standard form \(\frac{(x - h)^2}{a^2} - \frac{(y - k)^2}{b^2} = 1\), we can identify: - Center \((h, k) = (-1, -2)\) - \(a^2 = 16 \Rightarrow a = 4\) - \(b^2 = 9 \Rightarrow b = 3\) ### Step 5: Finding the Foci The foci of the hyperbola are given by: \[ (h \pm ae, k) \] where \(e = \sqrt{1 + \frac{b^2}{a^2}} = \sqrt{1 + \frac{9}{16}} = \sqrt{\frac{25}{16}} = \frac{5}{4}\). Calculating the foci: \[ Foci = (-1 \pm 4 \cdot \frac{5}{4}, -2) = (-1 \pm 5, -2) \] Thus, the foci are: \[ (-6, -2) \quad \text{and} \quad (4, -2) \] ### Step 6: Finding the Endpoints of the Latus Rectum The endpoints of the latus rectum are given by: \[ (h \pm ae, k \pm b) \] Calculating the endpoints: \[ Endpoints = (-1 \pm 5, -2 \pm 3) \] This gives: 1. \((-6, 1)\) 2. \((-6, -5)\) 3. \((4, 1)\) 4. \((4, -5)\) ### Step 7: Length of the Axes The lengths of the axes are: - Major axis length = \(2a = 8\) - Minor axis length = \(2b = 6\) ### Summary of Results - Center: \((-1, -2)\) - Foci: \((-6, -2)\) and \((4, -2)\) - Endpoints of the Latus Rectum: \((-6, 1)\), \((-6, -5)\), \((4, 1)\), \((4, -5)\) - Length of Major Axis: \(8\) - Length of Minor Axis: \(6\)
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