Document Sample

Inequalities in Triangles One or two? DAY 2 Inequalities in Triangles • Let’s do a discovery! • Materials: protractor, straight-edge • 1. Draw a scalene triangle. Label it ABC. • 2. Measure each side in cm and each angle in degrees. Mark this measures into the triangle. Inequalities in Triangles • 3. Complete the following chart: Large Large Med Med Small Small angle side angle side angle side • What conclusion can be made? • (This is not a profound answer.) Inequalities in Triangles • Let’s work with ONE triangle first… • If one angle of a triangle is larger than a second angle, • then the side opposite the first angle is longer than the side opposite the second angle. Inequalities in Triangles • Yes, it is just that straight forward. B • Name the largest to smallest angle. 9 11 A C B A 6 C Inequalities in Triangles • Name the largest B to smallest side. • Remember you can only work in ONE triangle at a time. A 80 60 40 C D BC DC BD AB AD Discovery 2 • Using triangle from Discovery 1, • Complete the following: lm s • lsm The sum of two sides of a • triangle is _____________ • m s l the third. • greater than Inequalities in Triangles • End of day one! • Homework: – Page 14 top #9 – 15 – Page 12 skip #14 - 17 Inequalities in Triangles • Day Two! • Let’s do a discovery: • Materials: Compass, rubber band, straight-edge • 1. Draw two non-congruent segment AB and BC so that you create an acute angle whose vertex is B. Measure length AB and redraw it with a dotted line forming an obtuse angle whose vertex is B. • 2. Place band on the ends of the compass. And set the ends on point A and C. Inequalities in Triangles • 3. Now stretch the width of the compass. Keep the same length for AB and BC. • 4. What happens to angle B? • 5. What happens to segment AC? • 6. What is true about segment AB ad BC? Inequalities in Triangles • Discuss with your group: • When comparing one triangle to another, what is true about the changing angle and side? Inequalities in Triangles • These theorems are just fun to read! • If two sides of one triangle are congruent to two sides of another triangle and the included angle of the first is larger then the included angle of the second, then the third side of the first is larger then the third side of the second triangle. Inequalities in Triangles • What does that B mean? E • Which must be D 60 • the bigger side? A 100 F C Inequalities in Triangles • How about this one? • If two sides of one triangle are congruent to two sides of another triangle and the third side of the first is larger then the third side of the second, then the included angle of the first is larger then the included angle of the second triangle. Inequalities in Triangles • What does that B E mean? D • Which must be 100 60 A • the bigger angle? F C Inequalities in Triangles • Homework: • Page 13 • Page 14 finish • Page 15

DOCUMENT INFO

Shared By:

Categories:

Tags:

Stats:

views: | 9 |

posted: | 12/13/2011 |

language: | Latin |

pages: | 16 |

OTHER DOCS BY 33e2LHO

How are you planning on using Docstoc?
BUSINESS
PERSONAL

By registering with docstoc.com you agree to our
privacy policy and
terms of service, and to receive content and offer notifications.

Docstoc is the premier online destination to start and grow small businesses. It hosts the best quality and widest selection of professional documents (over 20 million) and resources including expert videos, articles and productivity tools to make every small business better.

Search or Browse for any specific document or resource you need for your business. Or explore our curated resources for Starting a Business, Growing a Business or for Professional Development.

Feel free to Contact Us with any questions you might have.