Answer: 15
Step-by-step explanation:
Opposite angles of a cyclic quadrilateral are supplementary, so:

Answer:
None of the above
Step-by-step explanation:
=4+2y+7
x+8=(7x)+
(2y)+(4+8)=7x+2y+12
Answer:
C. ±square root of 30
Step-by-step explanation:
Apply the square root function to both sides of the equation:

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The absolute value equation has two solutions. They match choice C.