Answer:
<em>Is a tangent</em>
Step-by-step explanation:
<em>* Great question by the way *</em>
~ By definition, a tangent to circle is a straight line, presently perpendicular to a radius if one. In this case tangent AB should be perpendicular to the radius. If we were to call the center O, we would say AB should be perpendicular to OA. ~
1. Now let us say at the moment that AB is a tangent. If that is so, it should be that m∠A = 90 degrees ( ° ), provided AB is ⊥ to OA by definition.
2. Now the triangle ABO is a right triangle, and with that is should be that Pythagorean Theorem is applied. This can help us prove if AB is a tangent or not. If Pythagorean Theorem is not applicable it would mean ABO is not a right angle triangle, that AB is not ⊥ to OA, and thus can't be a tangent.
3. Let us say x ⇒ side OA, and that side BO = 9 + 8 + 17:
AB^2 + OA^2 = BO^2,
15^2 + x^2 = 17^2,
<em>x = 8</em>
4. Now there are two radii present, OA is only one of them. As radii are ≅, OA = other radii, 8 = 8
5. This proves that Pythagorean Theorem is applicable, that ABO is a right triangle, that m∠A = 90°, and that by definition <em>AB is a tangent</em>
