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Chapter 5 Section 7 Inequalities in Two Triangles. Objectives. Students will be able to apply inequalities in two triangles. Essential Understanding. In triangles that have two pairs of congruent sides, there is a relationship between the included angle the third pair of sides.
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Objectives Students will be able to apply inequalities in two triangles
Essential Understanding In triangles that have two pairs of congruent sides, there is a relationship between the included angle the third pair of sides
When you close a door, does the angle between the door and frame (at the hinge) get bigger or smaller?
The Hinge Theorem (SAS Inequality Theorem) If two sides of one triangle are congruent to two sides of another triangle, and the included angles are not congruent, then the longer third side is opposite the larger included angle
Using the Hinge Theorem What inequality relates LN and OQ?
Using the Hinge Theorem In ΔABC AB = 3, BC = 4, and CA = 6 In ΔPQR, PQ = 3, QR = 5, and RP = 6 How can you use indirect reasoning to explain why m<P > m<A?
Applying the Hinge Theorem The picture shows a pair of scissors in two different positions. In which is the distance between the tips of the two blades greater? Justify your answer.
Converse of the Hinge Theorem If two sides of one triangle are congruent to two sides of another triangle, and the third sides are not congruent, then the larger included angle is opposite the longer third side.
What is the range of possible values for x? First find the upper limit for the value of x by writing an inequality Second find the lower limit for the value of x by writing an inequality. Remember an angle has to be greater than zero Write the final answer as an inequality of the possible values
Using the Converse of the Hinge Theorem What is the range of possible values for x? Upper limit? Lower Limit?
Writing a Proof Given: <MON = 80, O is the midpoint of LN Prove: LM > MN
Homework Pg. 336 # 6 – 15, 23 11 problems