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what is the value of the other 2anglesif a trapezoid has 2 right angles?

My son has a math problem:  If a trapezoid has 2 right angles, what are the other 2 (ex accute and obtuse).

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JOHN B. | The BEST "All-Around" professional tutor for your needs.The BEST "All-Around" professional tuto...
4.8 4.8 (129 lesson ratings) (129)
A trapezoid is a quadrilateral. All quadrilaterals have four angles whose sum is 360 degrees. If two of the angles are right angles, that accounts for 180 degrees of the total. Therefore, the other two angles must total 180 degrees as well. Any combination of angles/degrees that equals 180 would work assuming the figure is closed and the object follows the rules of a trapezoid: A trapezoid is a quadrilateral with one pair of parallel lines. It could be imagined that one angle is Acute <90(but NOT including 90)degrees and the other Obtuse: an angle >90 (but NOT including 90)degrees and <180.


I'm voting 1.5 times for John's answer b/c

1. it is elegant and uses few words and

2. b/c he costs the least, but David, like an engineer, drew us apicture that helps explain the basic trapezoidal properties.

My answer, when in hS, would have been:

"They are any two complementary angles that add up to 180, except 90 and 90."

Daniel K. | Mathlete (Math & Sports)Mathlete (Math & Sports)

Draw an imaginery line to form a rectangle at the opposite end of the two right angles, within the trapezoid. This will give you an imaginary rectangle and an imaginary right triangle within your trapezoid. The sum of all angles in a triangle is 180 degrees. Just wanted to drop in another way of looking at the problem as most math problems have more than one way of finding the answer... If you are looking for actual values to those angles: Assuming you have at least 3 lengths of your trapezoid: use sin(angle)= opposite/hypotenuse; cos(angle)= adjacent/hypoteneuse; or tan(angle)= opposite over adjacent. Use the imaginary triangle you created, pick one of the odd angles, and your hypoteneuse will be the longest side of your triangle.

Douglas S. | Superior Academic TutoringSuperior Academic Tutoring
5.0 5.0 (3 lesson ratings) (3)
Joyce, your son has been presented with a "right" trapezoid, where two adjacent angles are right angles (90 degrees each). The sum of all four interior angles = 360. Because the two right angles = 180, the sum of the remaining two angles must = 180; one must be acute, the other obtuse.
Leslie P. | Enthusiastic & Fun tutor who works with all level students.Enthusiastic & Fun tutor who works with ...

Yes one angle would be acute ( less than 90) and the other would be obtuse ( greater than 90 degress)  however those two angles would add up to 180 degrees.  In a trapezoid you must have 2 parallel lines and 2 nonparallel lines   wish I could draw this.  In order to figure out the degrees of the other 2 angles I would need more info.   /___l  imagine a straight line going across the top too.  The right top and bottom angles are 90 degrees and the top and bottom lines are parallel .  The top left angle is acute and bottom left is obtuse the vertical left and right lines are not parallel .  Hope this helps :)


Leslie...It appears to me that the question was just looking for the total of the other two angles so you were correct just with the 180.