Given:
Given that O is the center of the circle.
AB is tangent to the circle.
The measure of ∠AOB is 68° and we know that the tangent meets the circle at 90°
We need to determine the measure of ∠ABO.
Measure of ∠ABO:
The measure of ∠ABO can be determined using the triangle sum property.
Applying the property, we have;
![\angle ABO+\angle BAO+\angle AOB=180^(\circ)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/rm7f90xy4i4wyoni4mwdvwxu87pbl6613n.png)
Substituting the values, we get;
![\angle ABO+90^(\circ)+68^(\circ)=180^(\circ)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/pyfp21ym8w88pg85de1ig8sgclulvjwx9c.png)
Adding the values, we have;
![\angle ABO+158^(\circ)=180^(\circ)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/q6sdiaa9h1o7b7vypbio071wzqdkiwc0w5.png)
Subtracting both sides by 158, we get;
![\angle ABO=22^(\circ)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/dqdjt38dkj8qq75tusgnmqnjxlrkhtxhlx.png)
Thus, the measure of ∠ABO is 22°