Question

In the fig. O is the center of the circle. What is the value of X ?​

Answer 1

ABCD is a quadrilateral.

Since it's inside a circle it's a cyclic quadrilateral.

In a cyclic quadrilateral, the opposite angles add up to 180°

which means angle B + angle D = 180° and angle A + angle C = 180°

since angle D = 150°

angle B = 180-150

angle B = 30°

x = 30°

hope it helps

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