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Recognizing angles

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Recognizing angles
Recognizing-angles 256
Exercise Name: Recognizing angles
Math Missions: 4th grade (U.S.) Math Mission
Types of Problems: 3

The Recognizing angles exercise is under the 4th grade (U.S.) Math Mission. This exercise practices classifying angles based on their measure as acute, right or obtuse.

Types of Problems

There are three types of problems in this exercise:

  1. Type of angle in polygon: This problem has a polygon and users have a couple tasks. First of all, they need to select how a particular angle compares to 90. Then they have to name that type of angle.

    Type of angle in polygon

  2. Type of angle in picture: This problem has a picture with an angle drawn in green. The user selects the type of angle that is in green.

    Type of angle in picture

  3. Select the angles: This problem has two intersecting lines drawn and the user is supposed to select all angles that are of a certain given type.

    Select the angles


This exercise is easy to get accuracy badges as long as user knows the acute ({<90^\circ}), right ({90^\circ}), and obtuse (>{90^\circ}) angles definitions. It is also easy to get speed badges because there are generally only three possibilities for most problems and any diagrams are easy to view and interpret.

  1. Concentrate on the green on problem type two. The picture is worth it!
  2. On problem type three the congruent angles are vertical angles. Therefore the answer will either be A and C, or it will be B and D (unless they eventually change the labels to give an extra wrinkle).

Real-life Applications

  1. Engineers and architects use angles for designs, roads, buildings and sporting facilities.
  2. Athletes use angles to enhance their performance.
  3. Carpenters use angles to make chairs, tables and sofas.
  4. Artists use their knowledge of angles to sketch portraits and paintings.

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