The answer is: [B]: " 15 " .
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Step-by-step explanation:
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"112" and "(7x + 7)" are the measurements of 2 (TWO) vertical angles;
and all vertical angles are equal; so, to solve for "x" ;
7x + 7 = 112 ;
Subtract "7" from EACH SIDE of the equation:
7x + 7 - 7 = 112 - 7 ;
to get:
7x = 105 ;
Now, divide EACH SIDE of the equation by "7" ; to isolate "x" on one side of the equation; and to solve for "x" ;
7x / 7 = 105 / 7 ;
to get: x = 15 ; which is:
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Answer choice: [B]: " 15 " .
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