​ Quadrilateral ABCD ​ is inscribed in this circle. What is the measure of angle B?

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I got 157, is my answer correct?

1 Answer
May 12, 2017

#157^0#

Explanation:

The shape is a cyclic quadrilateral, since all four vertices lie on the
circumference of the circle.

for a cyclic quadrilateral opposite angles add up to #180^0#

we have then

#x+6x+19=180#

#7x=180-19#

#7x=161#

#:.x=23^0#

to find angle B

#< B=6xx23+19#

#< B =138+19=157^0#

you are correct.