It doesn't have to, but it can. A trapezoid is any shape in which there is a pair of parallel sides. This means that a square can be classified as a trapezoid.
But notice that a four-sided shape can never have ONLY three 90° angles. The sum of angles of a four-sided shape is 360--this means that if you have three 90° angles, then the remaining angle must be 360-3(90) which is 90°, giving you four right angles.
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No you cannot. As indicated in the second paragraph of the above answer, three right angles implies that all four angles are right angles and that makes the figure a rectangle (or a square).
No
Yes. Those trapezoids with four right angles are called squares. Since in order to be a trapezoids, a shape must be a quadrilateral with with one set of parallel lines, and a square fits those requirements. In conclusion, the trapezoids that have four right angles are squares.
noIt has 2 obtuse angles and 2 acute angles though.
Certain quadrilaterals have right angles. Right trapezoids are the most general example. Rectangles are specialized right trapezoids, and squares are specialized rectangles. There may be more but I can't recall them. Many rhombuses and parallelograms have no right angles. However, they might (and then you'd probably call them squares or rectangles but they are also technically rhombuses, parallelograms and trapezoids).
No, because it would then be considered a rectangle.
Yes, a trapezoid can have 3 right angles.
No
Rhombuses and trapezoids have no right angles by definition.
Yes. Those trapezoids with four right angles are called squares. Since in order to be a trapezoids, a shape must be a quadrilateral with with one set of parallel lines, and a square fits those requirements. In conclusion, the trapezoids that have four right angles are squares.
noIt has 2 obtuse angles and 2 acute angles though.
Trapezoids do not have right angles. You probably thinking of a polygon or quadralateral.
Certain quadrilaterals have right angles. Right trapezoids are the most general example. Rectangles are specialized right trapezoids, and squares are specialized rectangles. There may be more but I can't recall them. Many rhombuses and parallelograms have no right angles. However, they might (and then you'd probably call them squares or rectangles but they are also technically rhombuses, parallelograms and trapezoids).
a trapezoid has no right angles whatsoever. no they cant because trapezoids have only 4 sides and dented
Because they don't have right angles.
No, because it would then be considered a rectangle.
Squares, rectangles, and some trapezoids.
Trapezoids actually have 5 angles (Including the straight angle).