Question

A circle k(O) with the radius r is given. Line AB tangent to circle k(O) at B. Find AB, if OA= 2 cm, and r=1.5 cm.

Answer 1

(√7)/2 ≈ 1.323

Explanation:

ΔABO is a right triangle with its right angle at B. Hypotenuse OA is 2, leg OB is 1.5, so leg AB will be given by the Pythagorean theorem as ...

AB = √(OA² -OB²) = √(2² -1.5²) = √1.75

AB = (√7)/2 ≈ 1.323