130 likes | 299 Views
Quadrilaterals Sec 6.1. GOALS: To identify, name, & describe quadrilaterals To find missing measures in quadrilaterals. Polygons. Polygon – a figure that has three or more sides. vertex. Specifically:. side. a plane figure a closed figure three or more noncolllinear sides
E N D
QuadrilateralsSec 6.1 GOALS: To identify, name, & describe quadrilaterals To find missing measures in quadrilaterals
Polygons Polygon – a figure that has three or more sides vertex Specifically: side • a plane figure • a closed figure • three or more noncolllinear sides • each side intersects exactly two other sides at the vertices
Polygon or not? Identify whether the following figures are polygons.
Naming Polygons Polygons are named by the number of sides they have. Number of sides Name 3 triangle 4 quadrilateral 5 pentagon 6 hexagon 7 heptagon 8 octagon 9 nonagon 10 decagon n n-gon
Convex and Concave Polygons Convex Polygon – a polygon where no line that contains a side of the polygon contains a point in the interior of the polygon. Point in the interior! Convex Polygon Concave Polygon
Example Name of Polygon Convex or Concave? #2 #1
Regular Polygon Regular Polygon – a polygon that is both equilateral and equiangular. Are the following polygons regular?
Diagonal of a Polygon A segment that joins two nonconsecutive vertices. Polygon ABCDE Diagonals BE and BD
Angle Measures in Quadrilaterals • The sum of the measures of the interior angles of a quadrilateral is 360 degrees. Theorem 6.1
Example • Find the value of y in quadrilateral WXYZ.
Example • Find the value of x in quadrilateral WXYZ. Then find the measure of angle X and Y.
Example • Solve for x and y. Then find the angle measures.
Homework • Page 325- See assignment guide