1 / 11

9/23/13 Warm Up

9/23/13 Warm Up . Q is between P and R . PQ = 2 w – 3 and QR = 4 + w, and PR = 34. Find the value of w , PQ , AND QR. Use the diagram to find the measures of angles 4 & 5. 68˚. Conditional Statement. A logical statement with 2 parts

lou
Download Presentation

9/23/13 Warm Up

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. 9/23/13 Warm Up • Q is between P and R. PQ = 2w – 3 and QR = 4 + w, and PR = 34. Find the value of w, PQ, AND QR. • Use the diagram to find the measures of angles 4 & 5. 68˚

  2. Conditional Statement • A logical statement with 2 parts • 2 parts are called the hypothesis & conclusion • Can be written in “if-then” form; such as, “If…, then…” • Hypothesis is the part afterthe word “If” • Conclusion is the part afterthe word “then”

  3. Ex: Underline the hypothesis & circle the conclusion. • If you are a brunette, then you have brown hair. hypothesis conclusion If two points lie on the same line, then they are collinear.

  4. Rewrite the statement in “if-then” form Ex 1: Vertical angles are congruent. If there are 2 vertical angles, then they are congruent. If 2 angles are vertical, then they are congruent. Ex 2: An object weighs one ton if it weighs 2000 lbs. If an object weighs 2000 lbs, then it weighs one ton. Ex 3: All monkeys have tails. If an animal is a monkey, then it has a tail

  5. Counterexample • Used to show a conditional statement is false. • It must keep the hypothesis true, but the conclusion false!

  6. Write a counterexample to prove the statement is false. Ifx2 = 81, thenx must equal 9. Counterexample: x could be (-9) because (-9)2=81, but x≠9. The hypothesis true, but the conclusion false!

  7. Counterexample Write a counterexample for the following statements: 1) If a number is divisible by 2, then it is divisible by 4. Counterexample: 10 is divisible by 2 but not 4. 2) If a bird is a swan, then it is white. Counterexample: A swan can also be black.

  8. Converse • Switch the hypothesis & conclusion parts of a conditional statement. • Ex: Write the converse of: • “If you are a brunette, then you have brown hair.” If you have brown hair, then you are a brunette.

  9. Write the CONVERSE of the statement 1) If there is snow on the ground, then flowers are not in bloom. Converse: If flowers are not in bloom, then there is snow on the ground. 2) If two segments are congruent, then they have the same measure. Converse: If segments have the same measure, then they are congruent.

More Related