Select the correct answer from each drop-down menu. B
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Points A B, and Cform a triangle. Complete the statements to prove that the sum of the interior angles of AABC is 180°.
Statement
Reason
Points A, B, and form a triangle.
given
Let DE be a line passing through Band parallel to AC. definition of parallel lines
23 25 and 2124
m_1 = m24 and 23= m25
m24+ m2 2 + 25 = 180°
angle addition and definition of a straight line
substitution
m21 + m2 2 + m23 = 180°