AC is tangent to circle o at point c. What is the length of AC? ___________ units. diagram below pls help

Answer:
AC = 4 units
Step-by-step explanation:
[tex] OB = OC = 3 (Radii \:of \:same \:circle) \\
OA = OB + AB = 3 + 2 = 5\\
OA \perp AC.. (tangent\: \perp radius) \\
\therefore m\angle OCA = 90\degree \\[/tex]
By Pythagorean theorem:
[tex] AC^2 = OA^2 - OC^2 \\
= 5^2 - 3^2 \\
= 25-9\\
= 16\\
AC =\pm \sqrt{16}\\
AC = \pm 4[/tex]
Since, side of a triangle can't be negative.
Therefore, AC = 4 units