Applying the inscribed angle theorem, the value of x is: A. 9
Based on the inscribed angle theorem, the measure of intercepted arc is twice the size of the inscribed angle in a circle.
Thus, considering the image attached below, applying the the inscribed angle theorem, we will have:
DF = 2(m∠DEF)
70 = 2(8 + 3x)
70 = 16 + 6x
70 - 16 = 6x
54 = 6x
9 = x
x = 9
Therefore, applying the inscribed angle theorem, the value of x is: A. 9
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