(17 points)
determine if line ab is tangent to the circle

1. If AB is tangent to the circle, then

We have

so AB is indeed tangent to the circle.

2. The unlabeled leg is another radius of the circle so it has length 8. Then if AB is tangent to the circle,

but we have

so that cannot be a right triangle and AB is not tangent to the circle.

angle uzt is congruent to angle tzy. angle vzw is congruent to angle yzx.

(credits to leowren)

step-by-step explanation: