convex
The extreme point it the highest or lowest point of the parabola (depending if it is concave downwards or upwards). It is the point of the parabola tat is closest to the focus. the extreme point lies on the axis of symmetry.
In a tessellation a number of polygons meet at a point. If n polygons meet, then there will be n vertices. These must add up to 360 degrees so that the tessellation does not leave holes. So the interior angles of the polygon must be a factor of 360 degrees. Interior angle of an equilateral triangle = 60 deg = 360/6 and so it will tessellate; Interior angle of a square = 90 deg = 360/4 and so it will tessellate; Interior angle of a regular pentagon = 108 deg which is not a factor of 360 and so it will not tessellate; etc.
On etymological grounds I would be tempted to call a 1000 sided polygon a myriagon. I will also point out that for most purposes we would call it a circle, since with that many sides it very closely approaches circularity.
If you mean point (2, 5) then it is in the 1st quadrant on the Cartesian plane
Write the equation in slope-intercept form of the line that has a slope of 2 and contains the point (1, 1).
concave polygon
It is concave.
concave
because the point of origin would be on an outer point and around it the walls seem to cave in making it seem concave, in comparison to a regular polygon. When checking for concave polygons always compare what you are looking at to a regular polygon
In a concave polygon a figure has an inverted point. This means all of the exterior angles do no = 360 and the interior angles do not follow the rule (number of sides - 2)180 to get the interior angle sum. Which is all important to geometry. To find out if a polygon is convex or concave take an imaginary rubber band and stretch it around the polygon. If it does not fit snugly then the polygon is concave. For instance if you had a giant square the rubber band would touch all four vertexes and have no gaps. A giant four sided V thought would have a gap between the two tips of the V and prove it was concave.
A concave quadrilateral
a convex polygon
It is a five sided polygon. At least one interior angle is greater than 180 degrees. This causes some of the vertices of the pentagon to point in toward the center. An alternate definition is there exists a line that will cut the polygon in 4 or more places.
A regular polygon has all its sides equal and all its angles equal. One consequence is that no angle can be reflex (between 180 and 360 degrees). A concave polygon, on the other hand, must have at least one angle that is a reflex angle. The line joining any two points inside any convex polygon (and that includes regular ones) must lie wholly within the polygon. In a concave polygon, it must be possible to find two point inside the polygon such that the line joining them crosses the boundaries of the polygon.
A convex polygon is defined as a polygon with all its interior angles less than 180°. This means that all the vertices of the polygon will point outwards, away from the interior of the shape. Think of it as a 'bulging' polygon. A triangle (3-gon) is always convex.
This has to do with the way in which the sum of the angles is derived. First you select a point inside the polygon and then join that point to each of the vertices. For a polygon with n sides, this gives rise to n triangles. The sum of the 3 angles of any triangle is 180 degrees. So the sum of the angles of all the triangles is n*180 degrees. Now, the "outer" angles of these triangles correspond to the interior angles of the polygon. But the sum also includes the angles formed arounf the central point. The sum of all the angles around this central point is 360 degrees. This is not part of the sum of the interior angles of the polygon and so must be subtracted. Thus, the interior angles of a polygon sum to n*180 - 360 degrees or 180*(n- 2) degrees.
A rectangular solid is a polygon, as it is a four-sided, six face object. In two dimensions, it will remain a polygon with intersecting lines at the interior, with no line exceeding the boudary of the edge of the object from any point of view.