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Quadrilateral types
Learn to identify quadrilaterals such as kites, trapezoids, parallelograms, rhombuses, rectangles, and squares by side length, presence of parallel sides, and angle type. Created by Sal Khan.
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- upvote pls! help me earn a badge!(34 votes)
- Is a square always a rombus?(11 votes)
- Yes, because a rhombus is a parallelogram with equal sides, and a square is also a parallelogram with equal sides.
The difference is that the square also has four right angles.
Rhombus
- 4 equal sides
- parallelogram
Square
- 4 equal sides
- parallelogram
- 4 equal 90° angles
Notice that the square - by definition - always meets the criteria for a rhombus. So every square is also a rhombus!
However, not every rhombus is a square: if the rhombus has 2 acute angles and 2 obtuse angles, then it is just a rhombus.
Hope this helps!(14 votes)
- ༎ຶ‿༎ຶ im fine ༎ຶ‿༎ຶ(7 votes)
- is there any proof that if a parallelogram has one right angle, it's a rectangle?(6 votes)
- Well, the definiton of parallelogram is that both pairs of sides are parallel - what I mean by pairs of sides is tricky to explain without a drawing, so I'm gong to assume you already know it. The diefinition of right angle is a measure of 90 deg, which means the two lines are perpendicular to each other. So with some logic you can see that if one line a is perpendicular to line b, and line c is parallel to line a, then line b has to be perpendicular to c as well. Right? And that means the angle between b and c has to be a right angle as well. You can keep going around the parallelogram and get four right angles, which means it's a rectangle(2 votes)
- soo, every shape with four sides is a quadriladeral?(5 votes)
- If the sides are connected to each other and are straight, yes.(3 votes)
- please help me with this stuff(6 votes)
- What is the type of this quadrilateral? 0:00Be as specific as possible with the given data. 0:02So it clearly is a quadrilateral. 0:05We have four sides here. 0:07And we see that we have two pairs of parallel sides. 0:09Or we could also say there are two pairs of congruent sides 0:13here as well. 0:16This side is parallel and congruent to this side. 0:17This side is parallel and congruent to that side. 0:20So we're dealing with a parallelogram. 0:23Let's do more of these. 0:26So here it looks like a same type of scenario 0:29we just saw in the last one. 0:31We have two pairs of parallel and congruent sides, 0:32but all the sides aren't equal to each other. 0:35If they're all equal to each other, 0:37we'd be dealing with a rhombus. 0:38But here, they're not all equal to each other. 0:39This side is congruent to the side opposite. 0:42This side is congruent to the side opposite. 0:44That's another parallelogram. 0:46Now this is interesting. 0:50We have two pairs of sides that are parallel to each other, 0:52but now all the sides have an equal length. 0:55So this would be a parallelogram. 0:58And it is a parallelogram, but they're 1:00saying to be as specific as possible with the given data. 1:02So saying it's a rhombus would be 1:05more specific than saying it's a parallelogram. 1:07This does satisfy the constraints 1:09for being a parallelogram, but saying it's a rhombus 1:11tells us even more. 1:13Not every parallelogram is a rhombus, 1:15but every rhombus is a parallelogram. 1:17Here, they have the sides are parallel to the side opposite 1:19and all of the sides are equal. 1:23Let's do a few more of these. 1:26What is the type of this quadrilateral? 1:28
•Current transcript segment:Be as specific as possible with the given data . 1:30So we have two pairs of sides that are parallel, 1:34or I should say one pair. 1:37We have a pair of sides that are parallel. 1:38And then we have another pair of sides that are not. 1:41So this is a trapezoid. 1:46But then they have two choices here. 1:48They have trapezoid and isosceles trapezoid. 1:49Now an isosceles trapezoid is a trapezoid 1:53where the two non-parallel sides have the same length, just 1:57like an isosceles triangle, you have 2:00two sides have the same length. 2:02Well we could see these two non-parallel sides do not 2:04have the same length. 2:07So this is not an isosceles trapezoid. 2:08If they did have the same length, then 2:10we would pick that because that would 2:12be more specific than just trapezoid. 2:13But this case right over here, this is just a trapezoid. 2:15Let's do one more of these. 2:19What is the type of this quadrilateral? 2:21Well we could say it's a parallelogram 2:23because all of the sides are parallel. 2:25But if we wanted to be more specific, 2:27you could also see that all the sides are the same. 2:28So you could say it's a rhombus, but you 2:31could get even more specific than that. 2:33You notice that all the sides are 2:34intersecting at right angles. 2:36So this is-- if we wanted to be as specific as possible-- this 2:38is a square. 2:42Let me check the answer. 2:45Got it right. 2:46(5 votes) - Im sure a kite is a quadrilateral that is shaped like a kite. You can search up different types of them.(2 votes)
- What is a trapezoid and isosceles trapezoid?(3 votes)
- Imagine starting with a triangle and cutting off the top parallel to the base of the triangle. That gives you a trapezoid which could be defined as a quadrilateral with exactly one set of parallel lines. Now if you start with an isosceles triangle with the base being the non-equal side, do the same thing and the two non-parallel sides are also congruent, so you have an isosceles trapezoid.
Trapezoids have different definitions and meanings depending on where you are in the world and which Math definition you choose. In Great Britain, what Americans call a trapezoid is called a trapezium (see http://mathworld.wolfram.com/Trapezium.html for some history), and an alternate definition of exactly one pair of parallel sides is given as AT LEAST one pair of parallel sides which would put all parallelograms under this definition. Sorry for the added confusion, but that is where Math is with the term.(6 votes)
- Just a quick question that's been on my mind:
Is it possible for any trapezoid to have the pair of parallel sides having equal length? If it did, it would be considered a square, right? But is a square considered a trapezoid? :/(4 votes)- No. By definition trapezoids will always have only one pair of parallel sides. Having a trapezoid with two parallel sides of equal length would give you two pairs of parallel sides, which would be considered a rectangle instead of a trapezoid. A square will also always have two pairs of parallel sides, and thus cannot be a trapezoid.(4 votes)
Video transcript
What is the type of
this quadrilateral? Be as specific as possible
with the given data. So it clearly is
a quadrilateral. We have four sides here. And we see that we have two
pairs of parallel sides. Or we could also say there are
two pairs of congruent sides here as well. This side is parallel and
congruent to this side. This side is parallel and
congruent to that side. So we're dealing
with a parallelogram. Let's do more of these. So here it looks like
a same type of scenario we just saw in the last one. We have two pairs of
parallel and congruent sides, but all the sides aren't
equal to each other. If they're all
equal to each other, we'd be dealing with a rhombus. But here, they're not
all equal to each other. This side is congruent
to the side opposite. This side is congruent
to the side opposite. That's another parallelogram. Now this is interesting. We have two pairs of sides that
are parallel to each other, but now all the sides
have an equal length. So this would be
a parallelogram. And it is a
parallelogram, but they're saying to be as specific as
possible with the given data. So saying it's a
rhombus would be more specific than saying
it's a parallelogram. This does satisfy
the constraints for being a parallelogram,
but saying it's a rhombus tells us even more. Not every parallelogram
is a rhombus, but every rhombus
is a parallelogram. Here, they have the sides are
parallel to the side opposite and all of the sides are equal. Let's do a few more of these. What is the type of
this quadrilateral? Be as specific as possible
with the given data . So we have two pairs of
sides that are parallel, or I should say one pair. We have a pair of sides
that are parallel. And then we have another
pair of sides that are not. So this is a trapezoid. But then they have
two choices here. They have trapezoid and
isosceles trapezoid. Now an isosceles
trapezoid is a trapezoid where the two non-parallel
sides have the same length, just like an isosceles
triangle, you have two sides have the same length. Well we could see these two
non-parallel sides do not have the same length. So this is not an
isosceles trapezoid. If they did have the
same length, then we would pick that
because that would be more specific
than just trapezoid. But this case right over here,
this is just a trapezoid. Let's do one more of these. What is the type of
this quadrilateral? Well we could say
it's a parallelogram because all of the
sides are parallel. But if we wanted to
be more specific, you could also see that
all the sides are the same. So you could say it's
a rhombus, but you could get even more
specific than that. You notice that
all the sides are intersecting at right angles. So this is-- if we wanted to be
as specific as possible-- this is a square. Let me check the answer. Got it right.