1) Vertical angles are pairs of non-adjacent angles formed when two lines intersect. They are always congruent. 2) When two lines intersect, they form four pairs of vertical angles. The measures of vertical angles always add up to 180 degrees. 3) Vertical angles have a common ray but different vertices. Statements about vertical angles being congruent or having measures that add to 180 degrees are true, while having a common vertex is false.

2. a. Find thevalue of any anglegiven the pairs of vertical angles;
b. Analyze statement aboutvertical angles;
c. Give reasons aboutstatementsinvolving vertical angles

3. 1. Draw a line in your bond paper and nameit as .
2. Draw anotherlineintersectingthe line and nameit as .
3. Namethe intersectionas Point E.
4. List theanglesformed by two intersectinglines.
5. Whatare thenonadjacentangles?
AB
suur
AB
suur
CD
suur

4. A
B
C
D
E

5. Two angles are vertical if and only if they are nonadjacentangles
formed by two intersecting lines.
and
Are vertical angles
and are vertical
A
B
C
D
EAED BEC
DEB CEA
angles

6. Vertical angles are congruent.
and
are congruent.
and
are congruent
A
B
C
D
E
AED BEC
DEB CEA

7. Directions: Analyze each following statement involvingvertical angles
whethereach statementis true or false.Write EJ if thestatement is
true otherwise write EB.
1. Vertical angles are two nonadjacentangles formed by a pair of
intersectinglines.
2. Two angles are vertical angles if their sides form two pairs opposite
rays.
3. Whentwo lines intersect, they form four pairs of vertical angles.
4. Sometimes thetotal measures of vertical anglesis 180 degrees.
5. Vertical angles have common ray but don’t have common vertex.

8. Directions: Give thereasons on thefollowingstatementsinvolving
vertical angles. Give one reason on each statement.Use ½ sheet of
paper.
In thefigureat theright, it is
given that .
1. Whyis ?
2. Why is ?
3. Why is ?
4. Whyis ?
5. Why is ?
3 8  
1 6  
4 7  
9 10  
12 11  
9 10
11
12
21
3 4
5 6
7 8
2 5  