The correct answer is x= -1. Hope this helps!!
Step-by-step explanation:
Quadrilateral ABCD is inscribed in a circle.
Opposite angles of a Quadrilateral are Supplementary.


+ 6 +

= 18
First, simplify

to

/ Your problem should look like:

+ 6 +

= 18
Second, simplify

to

/ Your problem should look like:

+ 6 +

= 18
Third, simplify

+ 6 +

to

+ 6 / Your problem should look like:

+ 6 = 18
Fourth, regroup terms. / Your problem should look like: 6 -

= 18
Fifth, multiply both sides by 7. / Your problem should look like: 42 - x = 126
Sixth, subtract 42 from both sides. / Your problem should look like: -x = 126 - 42
Seventh, simplify 126 - 42 to 84. / Your problem should look like: -x = 84
Eighth, multiply both sides by -1. / Your problem should look like: x = -84
Answer:
x = -84
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