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Look at this diagram. if DF and GI are parallel lines and m

Look at this diagram. if DF and GI are parallel lines and m-example-1
User Werner De Groot
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1 Answer

24 votes
24 votes

Vertical angles theorem or vertically opposite angles theorem states that two opposite vertical angles formed when two lines intersect each other are always equal (congruent) to each other.

∠FEH and ∠DEC are vertical angles, therefore


m\angle FEH=m\angle DEC=111^o

User Liviu Mandras
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