Friday, June 27, 2008

Geometry Quiz

Alright, I confess: I love math. I think since becoming a math teacher I'm an ever bigger dork.

This is a six question geometry quiz that we took today in my academy. I was the only one in my class that got the quiz entirely correct...Can you do it??? Read carefully and think! This isn't a brain teaser (or puzzle...Adam...), but it is tricky if you don't think each question through.

If you check the comment page, I will leave a hint (if you want one). This is a quiz intended to be given to an honors high school geometry class. Only 1 out of 25 math teachers, however, were able to complete it.

Your Directions: Tell which statements are true (that you agree with).

1) A rhombus is a square.

2) A square is both a rectangle and a rhombus.

3) A kite is a parallelogram.

4) Diagonals of all parallelograms bisect each other.

5) Diagonals are only congruent in a rectangle.

6) Diagonals always bisect each other in any rhombus or kite.

So, which are true???

~Mikey D

7 comments:

Mikey D said...

*** HINT ***

Of the six statements, three are correct.

Kevin said...

1: False. A square is rhombus, but not every rhombus is a square.

2: True

3: I need clarification. I've seen kite's in all shapes in sizes, and some of them were clearly not parallelograms. Or by kite do you mean the "diamond-shaped" kite? If it's a diamond, I say true I guess.

4: True

5: False. Because I already have 3 trues.

6: False. I forgot the defintions of most of these terms.

Man, it's been a loooong time since geometry class...

Mikey D said...

Haha, that's the way I've felt this entire past week.

A kite, by definition, is a quadrilateral with two pairs of adjacent sides that are congruent.

And the kite could be a "diamond-shaped" kite or a deltoid (concave)! As long as you can think of one example that disproves the statement.

***

2 and 4 are correct. One more, and it has to do more with semantics and logic than math...

Kevin said...

I didn't know that a kite was a mathematical shape. So then yeah, 3 is false.

6 is also false then, because the diagonals of a kite would not bisect each other.

But I say 5 is also false. Diagonals are congruent in several other shapes than rectangles. Such as an equilateral pentagon. (the diagonals form a star)

Kevin said...

The "or" in #6 is giving me trouble now. Is 6 true because the "or" always lets you choose the rhombus?

Adam said...

I originally said 2, 3, 4, and 6 were correct. Once I saw the hint, I said 2, 3, and 4 are correct.

So what's the correct answer?

Mikey D said...

2, 4, and 6 are correct.

Kevin, you were right on about #6. The diagonals in a rhombus always bisect each other, while in a kite they do not. Since it is an "or" statement, only one out of the two have to be true.

Adam, 3 is incorrect because in a kite adjacent sides have to be congruent, and not all parallelograms have adjacent sides congruent, so it is false.

Like I said, this was for an honor's geometry class, and since you guys haven't seen the stuff in years, I'd say you did pretty well!

Good stuff.