Obtuse. An acute angle is less than 90 degrees, a right angle is 90 degrees, and an obtuse angle is more than 90 degrees.
It is: "angle a is not a right angle" or "angle a is greater than or less than a right angle".
Right angle. An acute angle is less than 90°. An obtuse angle is more than 90°. If it isn't less than or greater than, it must be equal to. Of course a straight angle is more or less an extreme case of an obtuse angle.
Any closed shape with 6 line segments is a hexagon.
An angle smaller than a right angle - is an acute angle. Larger than a right angle, but smaller than 180 degrees is an obtuse angle. Angles between 180 and 360 degrees are reflex angles.
A four-sided shape with one right angle is a quadrilateral. There is no more specific term, unless it has more than one right angle or has equal sides.
No, if they did the shape would be a square. The angle is more than 90 degrees.
triangle
An obtuse triangle.
True a triangle can only have 1 right angle because it wouldn't be a closed shape with 2
A right angle triangle
It is a triangle
a rectangle
No, a triangle can not have more than one right angle.
No, a triangle can not have more than one right angle.
Depends on the shape. A right triangle has one right angle, a rectangle has 4, an equilateral triangle has none, a circle has no angles. There are polygons with more than 4 right angles, and there is no limit on how many, but those with more than 4 are not convex.
It is impossible for a triangle to have more than one right angle.