BFMracing
General Category => General Board => Homework Haven => Topic started by: Zeek on December 15, 2010, 02:10:09 PM
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ok this is one part i get real confused on is this.
Complete the statement with Always, sometimes, or never
a trapazoide is ________ a parallelogram. for this i am thinking always.
the base angles of an isosceles trapazoid______ congruent. for this i am thinking never
The legs of a Trapazoid are ________ congruent. For this im thinking always.
if im wrong plz correct me
Edit: second sentence was a typo
Edit2: the bases of a trapazoide are _______ parallel. i have no clue on this one
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#1. Never. Parallelograms have two pairs of parallel sides. A trapezoid will only ever have one.
#2. Always. Isosceles Trapezoids are the basic trapezoids. Top and bottom are parallel, legs are equal length and the there are two sets of congruent angles.
#3. Sometimes. The legs can vary in length depending on the trapezoid. An Isosceles Trapezoid will have congruent legs, but any other trapezoid can have vary leg lengths. For example, the awesome paint picture below shows two legs that aren't congruent.
(http://img192.imageshack.us/img192/8707/trapv.png)
#4. Not sure on this. I don't remember the exact definition of a base. If the base is always the parallel side, then the answer is Always...obviously. However, if the base is just the top and bottom sides, then the answer would be Sometimes. The next awesome paint picture shows why.
(http://img815.imageshack.us/img815/8462/trap2.png)
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ok thanks zakk.
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Trapezoids are never parrellelograms, to be a parrellelogram you must have 2 pairs of parrellel lines - a trapezoid only has one - the other pair is not parrellel.
the base angles of an isoosales triangle are both 45 degrees so would always be congruent since it follows that both sides would be equal length according to pythagorean theoram. I believe having equal sides is one of the definitions of congruency in a triangle.
Answer - always
For the legs of a trapezoid I would say sometimes, because only an Isosceles trapezoid would be congruent.
For the edited question on the bases of trapezoids I would GUESS sometimes, if the bases were the sides that were parrallel.
How did I do?
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Oh I see Zakk answered this also.
I was wrong on the bases question. Looked up the defintion - bases are the parrellel sides so it would be always.
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I should say that it depends on who your teacher is. Over here I'd probably say that a trapezoid is sometimes a parallelogram, since the definition I use is that a trapezoid has at least one pair of parallel sides. Which could mean also having a second pair. The definition I use comes from Wolfram's Mathworld and also makes a bit more sense since trapezoids also are used in calculus as a more general shape.
Incidentally, this means that rectangles and squares would also be called trapezoids.
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Now what would you say if we were calling them trapeziums :P
The idea of bases on a trapezoid that can have more than one pair of parallel sides would be nonsense, so it's safe to say that it's exactly one pair in these questions.
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Now what would you say if we were calling them trapeziums :P
The idea of bases on a trapezoid that can have more than one pair of parallel sides would be nonsense, so it's safe to say that it's exactly one pair in these questions.
I just figured that it would be simpler to call them "trapezoids" rather than introduce a new word. I think over here I'd talk about a "regular trapezium" but an "irregular trapezoid". Go figure.
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here are a few more questions. * this is a crosspuzzel.
Across
1.One way of representing a vector.
5.Describes how geometric figures of the same shape are related to one another.
13. Quantity that has both direction and magnitude.
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without knowing how many letters in each I can't do much more than guess, but 1 across might be "row" or "column", and 13 is almost certainly vector. Any letters for 5?
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in 1. there are 13 squares with the 4th letter a p and the last is an m.
5. there are 14 squares, 2 box is r, 6th is t 10. G 13. is o.
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1. might be something ending in "diagram" ?
5. transformation? doesn't quite fit the letters you had. symmetry, congruence, proportion(ate), amplitude...
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For myself I'm half wondering if you've got the letters right that you have got, because I'm stuck.