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Triangles and Parallel lines with Transversals - Printable Math Worksheets 8th Grade - Wayground

Triangles and Parallel lines with Transversals

Rachel Robinson

Created by Rachel Robinson

18 questions

8th Grade

Math

Updated Sep 2026

Triangles and Parallel Lines with Transversals is a Grade 8 mathematics worksheet that combines angle relationships formed by parallel lines and transversals with triangle classification and angle measurement. Students answer 17 multiple-choice questions and one fill-in-the-blank item by identifying alternate interior, corresponding, vertical, and alternate exterior angles; using supplementary-angle relationships; solving for missing angle measures; and recognizing isosceles, equilateral, and acute triangles. This worksheet helps students connect geometry vocabulary to visual diagrams and apply angle relationships instead of relying only on memorized definitions. The mix of selected-response and fill-in-the-blank questions gives teachers a quick way to check whether students can identify a relationship, calculate an unknown angle, and classify a triangle from its properties. It is a free printable worksheet with a complete answer key for Grade 8 math practice, review, or assessment.

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Triangles and Parallel lines with Transversals

Total questions: 18

Name
Class
Date
1.
Name the alternate interior angle to angle 3.
Name the alternate interior angle to angle 3.
a)
4
b)
5
c)
6
d)
8
2.
Find y.
Find y.
a)
50
b)
130
3.
Angle 1 = 27 o Find the measure of angle 4
Angle 1 = 27o
Find the measure of angle 4
a)
27o
b)
153o
c)
63o
d)
90o
4.
Identify each pair of angles.

Identify each pair of angles.

a)

vertical

b)

corresponding

c)

alternate exterior

d)

alternate interior

5.
Name the corresponding angle to angle 4.
Name the corresponding angle to angle 4.
a)
angle 8
b)
angle 6
c)
angle 2
d)
angle 5
6.
11) Given the two parallel lines cut by a transversal, What is the measure of if ?

11) Given the two parallel lines cut by a transversal,

What is the measure of ∠4\angle4  if  m∠8=76°m\angle8=76\degree  ?



(a)  

7.
Solve for angle 5
Solve for angle 5
a)
65
b)
60
c)
110
d)
115
8.
5) True or False. If the following parallel lines are cut by a transversal, would and be corresponding?

5) True or False.

If the following parallel lines are cut by a transversal, would 
∠2\angle2  and  ∠6\angle6   be corresponding?

a)

True

b)

False

9.
What are supplementary angles?
a)
Angles that add up to 180°
b)
Angles that add up to 90°
c)
Angles that are equal to each other
d)
Angles that are opposite of each other when lines intersect
10.
Find the missing angle.
Find the missing angle.
a)
29° 
b)
39° 
c)
49° 
d)
59° 
11.
Find the measure of each angle indicated.

Find the measure of each angle indicated.

a)

38

b)

47

c)

40

d)

70

12.
In the figure above, what is the value of ∠B?

In the figure above, what is the value of ∠B?

a)

60o

b)

20o

c)

100o

d)

120o

13.
What type of triangle is shown?

What type of triangle is shown?

a)

Isosceles

b)

Right

c)

Equilateral

d)

Scalene

14.
What type of triangle is shown?

What type of triangle is shown?

a)

Isosceles

b)

Right-angled

c)

Equilateral

d)

Scalene

15.
What Type of Triangle is this?

What Type of Triangle is this?

a)

Equilateral triangle

b)

Obtuse Triangle

c)

Acute Triangle

16.
Using what you know about vertical angles, Find the measure of angle a.

Using what you know about vertical angles, Find the measure of angle a.

a)

34°34\degree  

b)

143°143\degree  

c)

37°37\degree  

d)

72°72\degree  

17.
Find the measure of angle F

Find the measure of angle F

a)

A

b)

B

c)

C

d)

D

18.
Name the relationship and how their angle measures are related.

Name the relationship and how their angle measures are related.

a)

Corresponding, Congruent

b)

Corresponding, Supplementary

c)

Vertical Angles, Congruent

d)

None of These Options

WaygroundAnswer Key

Triangles and Parallel lines with Transversals

Total questions: 18

1.
b) 5
2.
b) 130
3.
a) 27o
4.
a)

vertical

5.
a) angle 8
6.
76
7.
a) 65
8.
b)

False

9.
a) Angles that add up to 180°
10.
b) 39° 
11.
c)

40

12.
a)

60o

13.
a)

Isosceles

14.
c)

Equilateral

15.
c)

Acute Triangle

16.
c)

37°37\degree  

17.
b)

B

18.
a)

Corresponding, Congruent

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FAQs

What does the Triangles and Parallel Lines with Transversals worksheet cover?

This Grade 8 worksheet covers angle relationships created when parallel lines are cut by a transversal, including corresponding, alternate interior, alternate exterior, and vertical angles. Its 17 multiple-choice questions and one fill-in-the-blank item also ask students to use supplementary angles, solve for missing measures, and classify triangles such as isosceles, equilateral, and acute triangles.

How can I use this worksheet to teach parallel-line angles and triangle classification?

Introduce the angle vocabulary with a labeled diagram, then model how a known angle can identify an equal angle or create a supplementary pair when parallel lines are cut by a transversal. Have students explain why they selected each relationship before completing the worksheet, and use the triangle questions afterward to connect angle and side properties to classification.

What mistakes should I watch for when students complete this worksheet?

Watch for students confusing corresponding angles with alternate interior or alternate exterior angles, especially when the angle positions look similar in the diagrams. Students may also treat supplementary angles as adding to 90° instead of 180°, or classify a triangle by a single visible angle without checking the defining side or angle properties.

How do I assign and grade this worksheet?

This worksheet is available as a printable PDF and as a digital quiz on Wayground, and it includes a complete answer key for checking the 18 responses. For printable submissions, you can scan student work with the Wayground for Teachers app to simplify grading and record results.

How can I differentiate this worksheet for my students?

Use the worksheet’s Advanced Settings to adjust font spacing or increase the font size so the angle diagrams, answer choices, and triangle questions are easier to read. You can also apply a dyslexia-friendly font or translate the worksheet into another language when those options support access to the geometry vocabulary and directions.

Where can I find more free worksheets like this on Wayground?

Wayground offers a comprehensive collection of free printable worksheets and practice problems across subjects, with downloadable PDFs and answer keys to help students master essential skills and concepts. Browse more resources at https://wayground.com/en-us/worksheets.

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