What is pt?

Question

1021 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-03-30T03:57:28

enter image source here

Given that PT is a tangent and PA is secant of a circle.

And #PB=4cm and BA=9cm#

We are to find out PT

Construction #T,B and A,T# are joined

#Delta BPT and DeltaAPT# are similar

Since

#angle BPT=angleAPT# common.

#angle BTP="alternate "angle PAT#

So

#(PT)/(AB)=(BP)/(PT)#

#=>PT^2=ABxxBP=9xx4#

#=>PT=6# cm