Question

In the figure "O" is the centre of the circle. Find x is LABC = 50°​

Answer 1

Answer:

$x + 50 + 90 = 180 \\ x + 140 = 180 \\ x = 180 - 140 \\ \boxed{x = 40°}$

Angle subtended by the chord passing through the diameter of the circle is always 90°.

Hence, angle C =90°

40° is the right answer.

Answer 2

Answer:

<ACB = 90° { angles in a SEMI-CIRCLE are 90°}

IN ∆ABC,

<BAC+<ABC+<ACB = 180° ( angle sum property)

x + 50 + 90 = 180

x + 140 = 180

x = 180-140

x = 40°