"z" has two acute angles a triangle can have 3 acute angles but also will have a angle >= 60degrees acute (also note for every acute angle a obtuse angle is formed the sum of the obtuse and acute angle will = 360) because of this a arrow is the only shape with two acute angles and 1 obtuse
polygon
4
no
An octahedron is a closed 3-d shape with 8 polygonal faces. There are 257 topologically different convex octahedra. In addition there are concave octahedra. Some of these will have no obtuse angles, others will have several.
"z" has two acute angles a triangle can have 3 acute angles but also will have a angle >= 60degrees acute (also note for every acute angle a obtuse angle is formed the sum of the obtuse and acute angle will = 360) because of this a arrow is the only shape with two acute angles and 1 obtuse
polygon
No there isn't
no....
4
a trapezoid :) * * * * * Not necessarily. A trapezoid can have two right angles, one acute and one obtuse angle. A parallelogram which is not a rectangle must have 2 acute and 2 obtuse angles.
no
No shape does. If it has 4 sides and one pair of parallel lines it cannot have only 1 right angle, it must either have: 1) 2 right angles, 1 acute acute and 1 obtuse angle; or 2) no right angles, 2 acute angles and 2 obtuse angles; in which case it would be a trapezium (trapezoid).
boomerang
A rhombus.
it is an irregular shape
An octahedron is a closed 3-d shape with 8 polygonal faces. There are 257 topologically different convex octahedra. In addition there are concave octahedra. Some of these will have no obtuse angles, others will have several.