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Recognizing triangle types
Recognizing-triangles 256
Description
Exercise Name: Recognizing triangle types
Math Missions: 4th grade (U.S.) Math Mission, 5th grade (U.S.) Math Mission, High school geometry Math Mission
Types of Problems: 3

The Recognizing triangle types exercise appears under the 4th grade (U.S.) Math Mission, 5th grade (U.S.) Math Mission and High school geometry Math Mission. This exercise practices the language of triangles including classification by sides and angles.

Types of Problems[]

There are three types of problems in this exercise:

  1. Select the correct category: This problem provides a chart with several triangles and two columns of possible classifications. The user is asked to correctly select the button to indicate which category is correct for each triangle.
    Rtt1

    Select the correct category

  2. Select the correct properties: This problem has a single triangle drawn and a list of several properties that may be true about the triangle. The user is asked to select all options from the list that are true about the triangle.
    Rtt2

    Select the correct properties

  3. Select the correct names: This problem provides a specific triangle and asks the user to select all appropriate names from a multiple select list.
    Rtt3

    Select the correct names

Strategies[]

Knowledge of the triangle vocabulary, specifically related to classification by sides or angles, is useful for this problem.

  1. Triangles are called acute, obtuse or right based on the measure of their largest angle.
  2. Triangles are called equilateral, isosceles or scalene based on the number of congruent sides (three, at least two, or none respectively).
  3. An equilateral triangle is automatically isosceles, as well as certain acute.

Real-life Applications[]

  1. Triangles will appear in the Pythagorean Theorem.
  2. Architects use triangles when building bridges, roofs on houses, and other structures.
  3. The ancient Egyptians from over 4000 years ago were very good at shapes and geometry. Every time the Nile burst its banks and flooded the planes, they had to use geometry to measure their gardens and fields all over again.