Question

If the circles x2 + y2 - 8x + 2y + 8 = 0 and (x-1)2 + (y-
3)2 = r2 have only one common tangent then :
O r = 2
O r = 8
O re(28)
O re(0, 2)​

Answer 1

Answer:

okhth jggfj kgtuol khtrdyk ohgdeti

Answer 2

Step-by-step explanation:

Correct option is

B

2<∣a∣<8

S

1

≡x

2

+y

2

−8x+2y+8=0

r

1

=

16+1−8

=

9

=3

S

2

≡x

2

+y

2

−2x−6y+10−a

2

=0

r

2

1+9−(10−a

2

)

We know the condition for two tangents that

Distance between centres <r

1

+r

2

⇒

(4−1)

2

+(−1−3)

2

<3+

10−10+a

2

3

2

+4

2

<3+∣a∣

⇒±5<3+∣a∣

When +ve sign is taken or when −ve sign is taken,

5<3+∣a∣ and −5<3+∣a∣

⇒∣a∣>2 and ∣a∣<8

Thus, 2<∣a∣<8