SME
Grade 10 Math · Geometry
Reasoning and proof: conditional statements and two-column proofs
Put the steps of a two-column proof in order, each with its reason, to show vertical angles are congruent.
Put in order
Put the proof that vertical angles are congruent in order.
1
?
2
?
3
?
4
?
5
?
Assumptions
•
Each line of a proof is a statement and its reason: a given, a definition, a postulate or a theorem proved before.
•
A line can only use lines above it.
•
Linear pairs are two angles that make a straight line: they add to 180°.
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