# Drawing Triangles (Part 2)

Warmup

Activity #1

Constructing a Triangle Given 3 Sides. If you get stuck, watch the video below.

• Use the Point tool to plot two points 6 cm apart.​
• Use the Segment tool to link the two points.​
• With A as center, draw a circle of radius 4 cm.​
• With B as center, draw another circle of radius 6 cm.​
• Use the Point tool to mark one of the points where the circles meet.​
• Use the Polygon tool to draw a triangle through the three points.​
• Use the Distance or Length tool to label the sides of the triangle.​
• Use the sliders to navigate the different possible triangles that can be created.

Activity #2

Triangle Construction. • Draw as many different triangles as you can with the following: One side measures 4 cm, another side measures 5 cm, and one angle measures 40°.

• Draw as many different triangles as you can with the following: Two sides measure 6 cm and one angle measures 100°.

(1.) Did either of these sets of measurements determine one unique triangle?

(2.) How do you know?

Activity #3

Triangle Construction. • Draw as many different triangles as you can with the following: One angle measures 50°, one measures 60°, and one measures 70°.

• Draw as many different triangles as you can with the following: One angle measures 50°, one measures 60°, and one measures 100°.

Challenge #1

Draw a 40° angle. Use a compass to make sure both sides of your angle have a length of 5 centimeters.

If you connect the ends of the sides you drew to make a triangle, is the third side longer or shorter than 5 centimeters? How can you use a compass to explain your answer?

Challenge #2

Using only the point, segment, and compass tools provided, create an equilateral triangle. You are only successful if the triangle remains equilateral while dragging its vertices around.

Quiz Time