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The line 4y - 3x + i=0 touches thecircle x' + y - 4x - 8y- 5=0 then i =? |
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Answer» -step EXPLANATION:If line 4y−3x+λ=0 touches the circle x 2 +y 2 −4x−8y−5=0 then distance of its centre from the line is equal to its RADIUS.Centre is (−2,−4)radius = 4+16+5 = 25 =5 units∴ 5= a 2 +b 2 AX 1 +by 1 +c 5= 16+9 ∣6−16+λ∣ ⇒5= 5∣−10+λ∣ ⇒ 5λ−10 =±5⇒λ−10=25⇒λ=10+10=355λ−10 =−5⇒λ−10=−25⇒λ=−15∴ λ=−15,25HOPE IT HELPS YOU |
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