Question

draw two tangent to a circle with radius 2.5 from an external point 10cm away from the centre of the
circle ​

Answer 1

Answer:

Construct a circle with radius =6cm and centre be C

Locate a point A which is 10 cm from C

Then find the perpendicular bisector of line joining points C and A. lets say the mid point will be M.

Now draw an 'another circle with centre at M and radius =6cm(2CA) and lets say this circle cuts the previous circle at 

points N and Q then draw the lines ABand AN which are our external tangents.

Sinces △CSA is right  angle triangle at L.S=90o

Therefore using pythagoras theorem

(CQ)2+(SN)2=(CA)2

(10)2−(6)2=(QN)2

QN=8cm is the length of  the tangent.



Answer 2

Answer:

Answer:

Construct a circle with radius =6cm and centre be C

Locate a point A which is 10 cm from C

Then find the perpendicular bisector of line joining points C and A. lets say the mid point will be M.

Now draw an 'another circle with centre at M and radius =6cm(2CA) and lets say this circle cuts the previous circle at 

points N and Q then draw the lines ABand AN which are our external tangents.

Sinces △CSA is right  angle triangle at L.S=90o

Therefore using pythagoras theorem

(CQ)2+(SN)2=(CA)2

(10)2−(6)2=(QN)2

QN=8cm is the length of  the tangent.