In the diagram below of PAO, AP is tangent to circle O at point A, OB = 7, and BP = 18.
What is the measure of line segment OA?
What is the measure of line segment OP?
What is the measure of line segment AP?
Since OB is also the radius, and is 7, the radius is 7, so OA is also the length of radius. \(\overline{OA} = 7\).
\(\overline{OP} = \overline{OB} + \overline{BP} = 7 + 18 = 25.\)
Lastly since \(\triangle OAP\) is probably right, so.. using the pythogoream theroem, the hypothenuse \(\overline{OP}^2 = \overline{OA} ^2 + \overline{AP}^2 = 25^2 = 7^2 + \overline{AP}^2 \)
Thus,
\(\overline{AP}^2 = 25^2 - 7^2 = 625 - 49 = 576\)
SO \(\overline{AP} = \sqrt{576} = 24\)
So those are your answers!
If you dont' understand anything feel free to ask!