Question

5.1/2 of 20 is equal to
(a) 10
(b) 20
(c) 40
(d) 22​

Answer 1

1/2 of 20 is equal to (a) 10.

Hope it helps you.

Answer 2

Correct option is

(3,−1)

equation of tangent to the

circle x

2

+y

2

=5 at (x

1

,y

1

)

will be xx

1

+yy

1

=5

x×1+y(−2)=5

x−2y=5 or x=(2y+5)

now this is tangent at

circle x

2

+y

2

−8x+6y+20=0

or (2y+5)

2

+y

2

−8(2y+5)+6y+20=0

or 4y

2

+20y+25+y

2

−16y−40+6y+20=0

or 5y

2

+10y+5=0

or y

2

+2y+1=0

(y+1)

2

=0

y=−1

∴x=2(−1)+5=3

∴ point at which tangent

is (3,-1)

⋆ wrong option