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The equation of the chord of the circle `x^2+y^2-3x-4y-4=0`, which passes through the origin such that the origin divides it inthe ratio 4:1, is`x=0`(b) `24 x+7y=0``7x+24=0`(d) `7x-24 y=0`A. `x=0`B. `24x+7y=0`C. `7x+24y=0`D. `7x-24y=0` |
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Answer» Correct Answer - 2 Let `y=mx` be a chord. Then the points of intersections are given by `x^(2)(1+m^(2))-x(3+4m)-4=0` `:. x_(1)+x_(2)=(3+4m)/(1+m^(2))` and `x_(1)x_(2)=(-4)/(1+m^(2))` Since `(0,0)` divides chord in the ratio `1:4`, we have `x_(2)= -4x_(1)` `:. -3x_(1)=(3+4m)/(1+m^(2))` and `4x_(1)^(2)=(-4)/(1+m^(2))` `:. 9+9m^(2)=9=9+16m^(2)+24m` i.e., `m=0,-(24)/(7)` Therefore, the lines are `y=0` and `y+24x=0` |
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