[size=150][color=#00ff00]REVIEW: 1&2: Draw a conclusion and name the Law.[/color][/size]
1. All stores sell something. Toys R Us is a store.
Given:[br][color=#00ff00]store -[/color]-> [color=#0000ff]sells something[br][/color][color=#00ff00]Toys R Us is a store[/color]Conclusion:[br] [color=#ff0000]Toys R Us sells something.[/color][color=#9900ff]Law of Detachment (If p-->q and p, then q.)[/color]
2. If Miles has money, then he can buy food. If Miles buys food, then he buys a sandwich.
Given: [color=#0000ff]Money[/color]-->[color=#ff7700] food[/color] and[color=#ff7700] food[/color]---> [color=#00ff00]sandwich[/color][br]Conclusion: [br] ([color=#0000ff]Money[/color] --> [color=#00ff00]sandwich)[/color][br][size=150][color=#ff0000]If Miles has money, then he buys a sandwich. [/color][color=#9900ff]Law of Syllogism (If p-->q and q-->r, then p-->r)[/color][/size]
[size=150]#3 Write in if-then form, and then determine the truth value. If false, state a counterexample.[/size]
Extra Review a)[br]Given this TRUE conditional, write another true statement:[br]If I'm sick, then I won't be there.
If I'm there, then I'm not sick. (the contrapositive)
Extra Review b)[br]Given this TRUE conditional, write another false statement.[br]If the lights are not off, then it is not dark.
If it's dark, then the lights are off. (the contrapositive)
Use the applet below to confirm these postulates:[br][br]Postulate 2.1 Through any two points there exists exactly one line.Postulate 2.2 Through any three noncollinear points there exists exactly one plane.[br][br][size=150][color=#0000ff](Remember to move the diagram around to look at the figure.)[br][/color][/size][br][color=#ff0000]*Can you draw a line through G and E?[br]*Can you draw a line through G, A, and C?[br]*Can you draw a line through G, F, and D?[/color][br][br][color=#9900ff]>Can you draw a plane through E, F, and D?[br]>Can you draw a plane through G, C, and E?[br]>Can you draw a plane through B, A, and C? (GeoGebra has trouble here...why?)[br]>Can you draw a plane through E, B, A, and C? (You'll have to choose 3 of the points to use [icon]/images/ggb/toolbar/mode_planethreepoint.png[/icon].)[br]>Can you draw a plane through E, A, G, and C?[/color]