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Identify and Classify Angles

Answer Keys Here

Aligned To Common Core Standard:

Grade 4 Geometry - 4.G.1

What are the Classifications of Angles? A major portion of mathematics is geometry. If you remember it is as important as mathematics itself. As much as it is interesting, it is required to understand all the angles that are a part of geometry. If you face problems identifying the angles, here's a small list for based on the classification of angles. Acute Angle - This is an angle whose measures equals to more than 0° but less than 90°. Measure the angle and if you find the measures less than 0 but greater than 90, know that it is an acute angle. All angles with 30°, 40°, 60° are acute angles. Right Angle - A right-angle has measure angles equal to 90°. They make a straight angle and that's why they are called right angles. Obtuse Angle - This angle has a measure of more than 90° however, less than 180°. This is called an obtuse angle. Straight Angle - When it comes to an angle whose measure equals 180°, it is called a straight angle. The above-mentioned angles will help you a lot in the geometry. These worksheets and lessons will help students identify acute, right, straight, and obtuse angles.

Printable Worksheets And Lessons

Homework Sheets

A real mix of geometry in here for you. We review some related standards, too.

  • Identify and Classify Angles Homework 1 - Is this angle acute, right, obtuse, or straight?
  • Lines or Line Segments HW 2 - A line goes without end in both directions. A ray has 1 endpoint and goes without end in 1 direction. A line segment has 2 endpoints.
  • Parallel or Perpendicular HW 3 - Parallel lines are lines on the same plane that can continue infinitely, but do not intersect (touch each other). If you check any point on parallel lines, they are always the same distance apart.

Practice Worksheets

Once again, line segments and lines sneak in here. The other 2 sheets focus on angles though.

  • Practice 1 - Classify Set Angles
  • Practice 2 - What is this? a) a line, b) a line segment, or c) a ray
  • Practice 3 - Classify the line set as intersecting, parallel or perpendicular.

Math Skill Quizzes

All you will find here are angles and line sets.

  • Quiz 1 - What is this?
  • Quiz 2 - Is this angle acute, right, obtuse, or straight?
  • Quiz 3 - Label the line sets.