Content code
m1224
Slug (identifier)
constructing-a-triangle
Parent content
Constructing Polygons
Grades
Secondary I
Secondary II
Topic
Mathematics
Tags
tracé
quotation
segment
compas
extrémités
rapporteur
triangle
constuire un triangle
dessiner un triangle
construction d'un triangle
Content
Contenu
Corps

​​​​​There are three ways to construct a triangle depending on the information given.

Links
Type
Anchor
Title
Method Using Three Side Measurements
Anchor
measurements-3-sides
Type
Anchor
Title
Method Using Measurements of One Side and the Two Angles Situated at its Endpoints
Anchor
measurements-side-and-two-angles
Type
Anchor
Title
Method Using Measurements of One Angle and the Two Sides That Form it
Anchor
measurements-angle-and-two-sides
Corps

It is important to know the properties of triangles to understand the constraints that must be respected.

Title (level 2)
Method Using Three Side Measurements
Title slug (identifier)
measurements-3-sides
Contenu
Corps

Use a compass and a ruler to draw a triangle when the measurements of its three sides are known.

Surtitle
Règle
Content
Corps

  1. Using a ruler, draw a line segment with the same measurement as one side of the triangle.

  2. Open the compass to a size that matches the other side of the triangle. Place the sharp point of the compass on one end of the line segment drawn in step 1. Draw a circle.

  3. Open the compass to a size that matches the third side of the triangle. Place the sharp point of the compass on the other end of the line segment drawn in step 1. Draw a circle.

  4. To form the triangle, draw two lines connecting the endpoints of the line segment drawn in step 1 to one of the two intersection points of the circles drawn in steps 2 and 3.

Corps

Refer to the following example.

Content
Corps

Draw a triangle with sides that measure |4\:\text{cm},| |5\:\text{cm}| and |7\:\text{cm}.|

  1. Using a ruler, draw a line segment with the same measurement as one side of the triangle.

  1. Open the compass to a size that matches to the other side of the triangle. Place the sharp point of the compass on one end of the line segment drawn in step 1. Draw a circle.

image

  1. Open the compass to a size that matches to the third side of the triangle. Place the sharp point of the compass on the other end of the line segment drawn in step 1. Draw a circle.

image

  1. Draw two lines that connect the endpoints of the line segment drawn in step 1 and one of the two intersection points of the circles drawn in steps 2 and 3 to form the triangle.
Title (level 2)
Method Using Measurements of One Side and the Two Angles Situated at its Endpoints
Title slug (identifier)
measurements-side-and-two-angles
Contenu
Corps

Using a protractor and a ruler, draw a triangle when the measurements of one of its sides and two of its angles are known. See the following method.

Surtitle
Règle
Content
Corps

  1. Using a ruler, draw a line segment with a measurement corresponding to the known side of the triangle.

  2. Using a protractor, draw one of the known angles of the triangle at one end of the line segment drawn in step 1.

  3. Again using the protractor, draw the other known angle of the triangle at the other end of the line segment drawn in step 1.

  4. Trace the angle formed by the lines drawn in steps 2 and 3 to form the complete triangle.

Corps

See the following for a more detailed example.

Content
Corps

Imagine drawing a triangle where one side measures |5\:\text{cm}| and the measurement of the two angles are |30°| and |70°.| Follow these steps.

  1. Using a ruler, draw a line segment with the same measurement as the known side of the triangle.

  1. Using a protractor, draw one of the known angles of the triangle at one end of the line segment drawn in step 1.

  1. Again using the protractor, draw the other known angle of the triangle at the other end of the line segment drawn in step 1.

  1. Trace the angle formed by the lines drawn in steps 2 and 3 to form the complete triangle.
Title (level 2)
​Method Using Measurements of an Angle and the Two Sides That Form it
Title slug (identifier)
measurements-angle-and-two-sides
Contenu
Corps

Using a protractor and a ruler, draw a triangle when the measurements of one of its angles and the two sides that form it are known. Follow these steps.

Surtitle
Règle
Content
Corps

  1. Using a ruler, draw a line segment that has the same measurement as a known side of the triangle.

  2. Using a protractor, trace a line to draw the known angle of the triangle at one end of the line segment drawn in step 1.

  3. Using the ruler again, identify the measurement of the second side of the triangle on the line drawn in step 2.

  4. Join the ends of the first and second line segments.

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