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Find the equation of the circle which passes through the points `(1,-2),(4,-3)`and whose center lies on the line `3x+4y=7.` |
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Answer» Let the equation of the circle be `x^(2)+y^(2)+2gx+2fy+c=0` (1) If (1) passes through the points (1,-2) and (4,-3), then `5+2g-4f+c=0` (2) and `25+8g-6f+c=0 ` (3) Since the center `(-g,-f)` lies on the line `3x+4y=7`, we have `-3g-4f=7` (4) Solving (2), (3), and (4), we get `g=-(47)/(15),f=(3)/(5)`, and `c=(11)/(3)` Substituting in (1), the equation of the circle is `15x^(2)+15y^(2)-94x+18y+55=0` |
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