Question

how is r = AB/2
please answer as soon as possible​

Answer 1

Step-by-step explanation:

According to a theorem, if a chord makes 90 degrees on the circumference of a circle the the chord is the diameter of the circle or the semicircle makes a right angle at any point on circumference.

so here AB makes a right angle on circumference

therefore we know the radius is half of diameter.

r = d/2

r =AB/2