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#1 2019-01-09 18:19:20

Registered: 2018-10-17
Posts: 5

Geometry Review

I need help checking my answers these questions are on my Geometry review of unit 1.

4. Write a counterexample for the converse of "Cats make great pets."

My answer; A lion is a cat, and it’s not a great pet.

6. Write a counterexample for the converse of "Cars have four wheels."

My answer; The motorcycle is a car, and it has two wheels.

Some background; Counterexample is when the hypothesis is true that proves the conclusion is wrong.

my teachers response was,"These are incorrect. Please state the converse first so I'm sure you are finding the counterexample for the correct sentence."

I believe she is just intending for me to put the converse of this statement which would be "If it’s a great pet, then it’s a cat." and the converse for #6, "If it has four wheels, then it’s a car."

I could just be over analyzing what she is trying to say and all I have to do is include the converse statement in my answer? What do you guys think? smile


#2 2019-01-09 21:15:04

Registered: 2005-06-28
Posts: 26,621

Re: Geometry Review

Hi Lauren1415,

#4 is True. For example, Leopard is a cat but it is not a great pet. Similarly, Cheetah is also a cat but it isn't a great pet.

#6. The rule is 'Motorcars have four wheels' or 'Cars have four wheels' is the rule. Exceptions:



A motorcycle necessarily has two wheels, in rare cases, three wheels. Certainly, not four.

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi. 

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.


#3 2019-01-10 04:52:44

Registered: 2018-10-17
Posts: 5

Re: Geometry Review

thank you


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