Two angles that have the sum of 180 degrees are supplementary angles. Given one supplementary angle A, a person can find the other supplementary angle B by subtracting A from 180 degrees.
Know MoreIf one of the supplementary angles is 40, then the other supplementary angle is 180 – 40, or 140 degrees. When added together, two supplementary angles also form a straight angle; thus, a straight angle is also equal to 180 degrees.
In geometry, there are other different types of angles besides supplementary angles, such as acute and obtuse angles. While an acute angle is less than 90 degrees, an obtuse angle is more than 90 degrees but less than 180 degrees. In the example given above, the 40-degree angle is an acute angle, and the 140-degree angle is an obtuse angle.
Learn more about ShapesThe sum of the interior angles of an equilateral triangle equals 180 degrees. This stems from the fact that the combined interior angles of any given triangle always add up to this same amount, according to the Monterey Institute for Technology and Education.
Full Answer >A ray that divides an angle into two congruent angles is called an angle bisector. The straight line cuts an angle in half, creating two equal angles.
Full Answer >Two types of geometric quadrilaterals, rectangles and squares, have two pairs of parallel lines and four right angles. In terms of these two shapes, they differ in that a square's sides are all equal length, whereas a rectangle generally has one longer pair and one shorter pair.
Full Answer >Most rhombuses do not have right angles, but a square is technically a rhombus and does have right angles at each of its corners. A rhombus is defined by having four sides of equal length, where opposite sides run parallel to each other, and opposite angles are equal. A square fulfills all these conditions.
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