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Grade 12th passAlgebra

find the equation of a tangent line to ellipse 9x^2+25y^2=225 at x=3

Profile image of Mahbub Shariff
12 Years agoGrade 12th pass
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1 Answer

Profile image of Rinkoo Gupta
12 Years ago
put x=3 in eq. of the ellipse
9(9)+25y2=225
81+25y2=225
25y2=144
y2=144/25
y=12/5
so the touching point is (3,12/5)
eq. of the ellipse can be written as x2/25 +y2/9 =1
noq eq of the tangent to the ellipse at point (3,12/5) is
3x/25 +12y/45=1
27x+60y=225 Ans.
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Rinkoo Gupta
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