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The sum of the 4 internal angles of a quadrilateral must sum to 360° (go look up the proof of this elsewhere).
For the sake of argument, let's call the 4 internal angles of a quadrilateral A, B, C, and D.
If they were all obtuse, then (by definition):
180° > A > 90°
180° > B > 90°
180° > C > 90°
180° > D > 90°
If you add them all up, you find that for the sum of the angles A+B+C+D
720° > A + B + C + D > 360°
but, A+B+C+D = 360°,
Since the assumption produces a result that contradicts this, the assumption cannot be true.
Q.E.D.
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What is the name of the Quadrilateral with only right angles?
A quadrilateral is any shape with four sides; angles can be acute or obtuse. A perfect square is the only quadrilateral with only right angles.
Why can't a quadrilateral have no more than three obtuse angles?
The sum of all the interior angles of a quadrilateral is 360 degrees. If it had more than three obtuse angles, then it would have all four angles greater than 90 degrees so that their sum would be greater than 360 degrees.
Why can't a quadrilateral have more than three obtuse angle?
because if it has more than three obtuse angles than its not a quadrilateral.This is because a quadrilateral has 360 degrees, right? Well an obtuse angle is an angle greater than 90 degrees. That being said the smallest obtuse angle you can have is 91 degrees. If you have four obtuse angles, then the sum of them is greater than 360 (ex: 91+91+91+91=364) and it's geometrically impossible to draw a quadrilateral with 4 obtuse angles.Three obtuse angles are possible if the fourth is acute(less then 90 degrees) and they all add up to 360.-skerr7464
What do the four angles in a quadrilateral add up to?
All four of the interior angles of a quadrilateral add up to 360 degrees.
Does a kite have any obtuse angles?
Assuming the kite has four sides and is not a square, then yes, it must have obtuse angles.
How many obtuse angles can a quadrilateral have?
3 you cant draw one with four
Is it possible to have a quadrilateral with four obtuse angles?
No, a quadrilateral couldn't have four obtuse angles because the four interior angles of a four-sided quadrilateral add up to 360 degrees, and the sum of the measures of four obtuse angles would be greater than 360 degrees.
What is the maximum number of obtuse angles a quadrilateral can have?
Well, what i thought was that a definition of a quadrilateral is a shape that has four angles.
Can trapezoids have four obtuse angles?
No, because the total sum of angles in a quadrilateral are 360 degees.
What is the name of the Quadrilateral with only right angles?
A quadrilateral is any shape with four sides; angles can be acute or obtuse. A perfect square is the only quadrilateral with only right angles.
What quadrilateral can have four congruent sides and at least two obtuse angles?
a paralelagram
Can a trepoize have a four obtuse angles?
No because the total angles in a quadrilateral must not exceed 360 degrees.
If you know that two of the angles in a quadrilateral are obtuse then what is true about the other two angles and Explain?
You know that at least one of them must be acute. A quadrilteral can have three obtuse angles, but not four.
Does a rectangle have 2 acute and 2 obtuse angles?
NO!!! All four angles are right-angles (90 degrees) The word 'rectangle' means -right-angled quadrilateral.
How is a rhombus different from a quadrilateral?
It is no different from a quadrilateral.A quadrilateral is any shape with four sides and a rhombus has four sides, therefore it is a quadrilateral.
Why can't a quadrilateral have no more than three obtuse angles?
The sum of all the interior angles of a quadrilateral is 360 degrees. If it had more than three obtuse angles, then it would have all four angles greater than 90 degrees so that their sum would be greater than 360 degrees.
How much obtuse angles does a rectangle have?
It has none because a rectangle has 4 equal interior angles of 90 degrees
