Question

in figure, X Y and X' Y' are two parallel tangents to a circle with centre O and another tangent AB with point of contact C intersecting X Y at A X' Y' at B. Prove that angle AOB= 90 degree

Answer 1

Follow these steps to do the question -
draw the diagram
draw triangle AOB
then mark the angles which are at right angle and the test angles numbering
now ,
use the law of interior angles to find equal angles
then compare the equations , you will get the answer
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