Alternate Interior Angles
true
The centroid, circumcenter and orthocenter are the 3 points of concurrency that always lie on a line.
SOMETIMES. I just did that problem in my California geometry book. They can either be parallel or skew...making the answer sometimes.
Well honey, a 27-sided polygon has 27 interior angles. To find the sum of those angles, you use the formula (n-2) * 180, where n is the number of sides. So, for a 27-sided polygon, you'd have (27-2) * 180 = 4,860 degrees. Math doesn't lie, darling.
The orthocenter of a triangle may lie outside the triangle because an altitude does not necessarily intersect the sides of the triangle.
sides
It must be an obtuse angled triangle.
No.
The orthocenter of a triangle may lie outside the triangle since the ___altitude___ may not intersect any side of the triangle. * * * * * No. One of the altitudes must intersect the side opposite it and so it is not correct to say ANY side of the triangle.
The interior angles of a triangle must lie within the range (0, 180) degrees. For all other polygons, the interior angles must be in the range (0, 360) excluding 180 degrees.
All three medians MUST lie inside the triangle.
Not normally
Those are "alternate interior" angles. They're always equal.
The complement of the triangle in the plane.
Alternate Interior Angles
No, it cannot.