2. C-1: Linear Pair:
If 2 angles form a linear pair then they add up to
180°
1 2
< 1 + < 2 = 180°
3. C-2: Vertical Angles:
If 2 angles are vertical then, they are congruent
2
1 3
4
<1 ≅< 3 and <2 ≅<4
4. If you accept Linear Pair conjecture then
thru DEDUCTIVE Reasoning-you can prove
that Vertical angles are ≅ .
1
4 2
3
Linear Pair: <1 + <2 = 180° If true then other angles
<2 + <3 = 180° must be ≅ . ΤΗΙΝΚ!
<3 + <4 = 180° <2 = <4 therefore:
<4 + <1 = 180° <1 must = <3 and so on.
5. Note: Protractors will NOT work for these
problems!!
You MUST know the rules to solve!
Try it!
1
52° 2
3
m< 1 = Why?
m< 2 = Why?
m< 3 = Why?
Your perspective matters!!
