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Q: A: ### Quick Answer

**A quadrangle with one right angle has no special name.** It is called a quadrangle or a quadrilateral. Any four-sided shape is a quadrilateral, according to Math Is Fun.

The types of quadrangles that have special names are rectangles, parallelograms, rhombuses, squares, trapezoids and kites. Quadrangles must have interior angles that total 360 degrees. A rectangle has four right angles, and each angle is 90 degrees. A parallelogram does not necessarily have right angles, but opposite angles need to be equal, similar to the rhombus. An isosceles trapezoid has equal angles that come from parallel sides. A kite has equal angles where the two pairs of sides intersect.

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## What is the tangent formula?

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Full Answer >**The formula for the tangent of an angle, x, is tan(x) = opposite / adjacent, where opposite and adjacent refer to the sides of a right angle triangle containing the angle x.**Another formula for the tangent of an angle is tan(x) = sin(x) / cos(x).Filed Under: - Q:
## How do you calculate the area of an obtuse triangle?

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Full Answer >**To find the area of a triangle without a right angle, you multiply one-half the base by the height.**Obtuse triangles are included in this group.Filed Under: - Q:
## What is the exterior angle theorem?

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Full Answer >**The exterior angle theorem states that an angle exterior to a triangle equals the sum of the two angles not adjacent to it.**The theorem’s basis derives from the fact that the sum of all the interior angles in a triangle equals 180 degrees.Filed Under: - Q:
## What is an orthogonal vector?

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Full Answer >**An orthogonal vector is a vector that is at an angle of 90 degrees, or perpendicular, to another vector.**Up to three vectors can be mutually orthogonal to each other in a three-dimensional space.Filed Under: