00:01
Okay, this is problem number 20.
00:03
And what they give us is they are giving us pb is equal to a -b and they're equal to five.
00:22
They're also giving us pd equals four.
00:27
They're asking us to find pt and they're also asking us to find pc.
00:38
Okay.
00:39
We are going to set pc equal to x.
00:46
So what we know is pb plus ab is going to equal pa.
00:59
So we know that 5 plus 5 is going to equal to 10.
01:06
So pa equals 10.
01:14
So we also know that when a secant segment and a tangent segment are drawn to the circle from the same external point, in this case it's p.
01:26
The product of the sequence segment and its external segment is going to equal to the square of the tangent.
01:32
So what that saying is pt squared is going to equal pd times p .c...