ab is tangent to circle O at point a and mAC = 58 what is m<abc
Since AB is tangent to circle O at point A, we know that angle ABC is a right angle. This is because a tangent to a circle at a point is perpendicular to the radius of the circle at that point.
Since angle ACB is 58 degrees, and angle ABC is a right angle, angle ABC = 90 - 58 = 32 degrees.
Therefore, m<ABC = 32 degrees.