Copying and Constructing Triangles

Math 2 - Lesson 59Mr. Lopez

Construction an Equilateral Triangle

Given: AB

Construct: Equilateral Triangle XYZ using AB as its lengths

1. Draw an ray from X longer than AB.

2. Using your compass, get the width of AB.

3. Using the same compass settings, place the point of the compass on X and make an arc that starts above X and passes through the ray. Mark the intersection Y.

4. With the same compass setting, place the point of the compass on Y and make an arc that starts above Y and passes through 1st arc. Mark the intersection Z.

5. Connect X to Z and Y to Z to complete the equilateral triangle.

Construction an Equilateral Triangle

• Try: Given: AB Construct: Equilateral XYZ using AB

A B

X Y

Z

Copying Triangles

Given: ABC and ray X

Construct: XYZ so that it is congruent to ABC

1. Use your compass and record the width of AB.

2. Keeping the compass setting, place the point on X and make an arc that passes through the ray. Label this intersection Y.

3. Use your compass and record the width of BC.

4. Keeping the compass setting, place the point on Y and make an arc above Y.

5. Use your compass and record the width of AC.

6. Keeping the compass setting, place the point on X and make an arc above X so that it intersects with other arc. Label this intersection Z.

7. Use your straightedge to complete the triangle.

XA B

C