Identifying Pairs of Angles
Statements & Reasons
Write the justification
Justifications with
parallel lines
parallel lines
Finding measures given parallel lines
100
Angles 3 & 6 are this type of angle pair.
What are same side interior angles.
100
What can you conclude from the following and why? ... X is between D and F
What is DX + XF = DF by the segment addition postulate.
100
Statement Reason
1. <BAC is congruent to <CAD Given
2. __________ Definition of an
angle bisector
What is ray AC bisects <BAD?
100
Given that lines m & l are parallel, this theorem/postulate allows us to conclude that m<2 = m<8.
What is the alternate exterior angle theorem?
100
If segment XY is parallel to segment ZW, what is the measure of angle 5 and why?
What is ... m<5 = 154 degrees by the corresponding angles postulate.
200
Angles 5 & 3 are this type of angle pair.
What are alternate interior angles?
200
What can you conclude and why ... M is the midpoint of PQ.
What is ... PM is congruent to MQ by the definition of a midpoint.
200
Statement Reason
1. Angle 1 and Angle 2 are 1. Given
complementary
2. m<1 + m<2 = 90 2. _____
What is the definition of complementary angles
200
Given that m<4 + m<5 = 180, this theorem/postulate allows us to conclude that lines m and l are parallel.
What is the converse of the same-side interior angle theorem?
200
Given the lines are parallel and cut by transversal t, find the value of x and why?
What is ... x = 30 by the corresponding angles postulate.
300
Angles 1 & 7 are this type of angle pair.
What are alternate exterior angles?
300
What can you conclude and why? ... AB = DF and BC = DF
What is ... AB = BC by the Substitution Property of = or transitive property of equality
300
Statement Reason
1. Seg BC is congruent to 1. Given
Seg DE
2. BC = DE 2. _________
What is the definition of congruent segments
300
Given lines m & l are parallel, this theorem/postulate allows us to conclude that m<4 = m<8.
What is the corresponding angle postulate?
300
What is the value of x and why?
What is x = 17 by the alternate interior angle theorem?
400
Angles 1 & 5 are this type of angle pair.
What are corresponding angles?
400
What can you conclude and why? ... ray BC bisects angle ABD
What is ... <ABC is congr to <CBD by the definition of an angle bisector
400
Statement Reason
1. An X if formed by two lines. 1. Given
2. Angles opposite each 2. ____________
other are congruent.
What is the vertical angle theorem?
400
Given m<4 = m<6, this theorem/postulate allows us to conclude that lines m and l are parallel?
What is the converse of the alternate interior angle theorem?
400
What is the value of x and why?
What is x = -10 by the same side interior angle theorem?
500
Angles 2 and 4 are this type of angle pair.
What are vertical angles?
500
What can you conclude and why? ... Angle 1 and angle 2 are supplementary
What is ... m<1 + m<2 = 180 by the definition of supplementary angles
500
Statement Reason
1. Angle XYZ is a right angle 1. Given
2. m<XYZ = 90 2. ____
What is the definition of a right angle?
500
Given that m<2 = m<4, what, if anything, can we conclude about lines m and l?
What is nothing. We can conclude nothing about lines m and l.
500
Given parallel lines cut by a transversal, what is the value of x?
What is x = 20?