The tangents AB and AC are drawn from the point to the circle with the center O.
The tangents AB and AC are drawn from the point to the circle with the center O. Find the distance between points O and A, IF AC = 14cm and angle A = 120
Let’s construct the radii OS and OB to the points of tangency C and B.
The radii drawn to the points of tangency are perpendicular to the tangents themselves, then the triangles AOB and AOC are rectangular.
In right-angled triangles AOB and AOC, the hypotenuse OA is common, OB = OC = R, then the triangles AOB and AOC are equal in leg and hypotenuse, then the angle OAB = OAC = BAC / 2 = 120/2 = 60.
In a right-angled triangle AOC, the angle AOC = 90 – 60 = 30.
The AC leg lies opposite an angle of 30, then its length is equal to half the length of the OA hypotenuse.
OA = 2 * AC = 2 * 14 = 28 cm.
Answer: Between points O and A 28 cm.