It is impossible for a triangle to have 2 angles of 90 degrees
12 exterior angles that add up to 360 degrees 12 interior angles that add up to 1800 degrees
1800 degrees (that is the sum of the internal angles of the 12-sided polygon).
There's a really handy little formula. The total number of degrees in a polygon (the sum of the interior angles) is equal to (2n-4) right angles or (2n-4)x90 degrees. So for an octagon, the sum of the interior angles is 2x8-4 right angles = 16-4 right angles = 12 right angles or 12x90 degrees = 1080 degrees. To find one angle, divide this by 8 and you get 135 degrees.
12
Any polygon can have two interior angles of 12 degrees. No polygon can have all its interior angles of 12 degrees.
It is impossible for a triangle to have 2 angles of 90 degrees
12 exterior angles that add up to 360 degrees 12 interior angles that add up to 1800 degrees
12 right angles.
A dodecagon is a 12 sided shape that has 12 interior angles that add up to 1800 degrees and 12 exterior angles that add up to 360 degrees
a rectangle has 4 right angles.
The 12 interior angles add up to 1800 degrees
If one of its exterior angles is 30 degrees, then it is a star with 6 points and 12 sides. 360 degrees / 30 degrees = 12 angles It is a regular dodecahedron.
12
1800 degrees (that is the sum of the internal angles of the 12-sided polygon).
It has 12 of them.
There's a really handy little formula. The total number of degrees in a polygon (the sum of the interior angles) is equal to (2n-4) right angles or (2n-4)x90 degrees. So for an octagon, the sum of the interior angles is 2x8-4 right angles = 16-4 right angles = 12 right angles or 12x90 degrees = 1080 degrees. To find one angle, divide this by 8 and you get 135 degrees.