Chapter 6.1 POLYGONS

 Draw a picture of a polygon on each of your post-it notes.  Try to draw two different types of polygons (be creative).  Post them on the far wall (under “Polygons” sign) DRAW AND POST

 Take a minute to think about your drawings, what makes a figure a polygon?  Pair up with someone and share your thoughts. (Be sure to listen to their thoughts as well.)  Write down properties you think must exist to call something a polygon. THINK/PAIR/SHARE

Polygons Not Polygons SECTION 6.1 WHAT IS A POLYGON? (WRITE DOWN)

 Three or more sides  No curved sides  Each segment connects to only two others (segments don’t cross) A POLYGON HAS…(WRITE DOWN)

 Ones - come up the board and remove any examples from the wall that you think are not polygons and put them on the table in front of the computers.  Twos – Check to see if you agree with the drawings that were removed. Then go to the wall and make sure that Group 1 removed all the drawings that should have been removed. DECIDE AND CHECK

Convex Polygons CONVEX VS CONCAVE (WRITE DOWN) Concave Polygons

Convex Polygons WHAT’S THE DIFFERENCE? Concave Polygons

 Twos– Go to the wall and divide the drawings into two groups (Concave/Convex)  Ones – Check to see that the Twos grouped the drawings correctly DECIDE AND CHECK

 If all the angles in a polygon are equal it’s called  If all the sides in a polygon are equal it’s called  If a polygon is both equilateral and equiangular it is regular (write down) equiangular equilateral

 Polygon Names Polygon Names POLYGON NAMES

 Ones – Go to the wall and label all the Concave drawings with the appropriate name.  Twos – Go to the wall and label all the Convex drawings with the appropriate name. DECIDE AND CHECK

 A diagonal connects two non- consecutive vertices (write down) DIAGONALS

 A rectangle has 2 diagonals  Draw the diagonals of a pentagon (5 sides) DIAGONALS

PENTAGON

 In your notes create a table, the size of a full sheet of paper, that has 4 columns and 12 rows. Leave enough room to draw a picture below the name. TRIANGLES IN A POLYGON Name# of sides# of trianglesInterior Angle Sum Triangle31180 Quadrilateral …. Dodecagon n-gon nn - 2 (n – 2) x 180

 x=360  253+x=360  X=107 SOLVE FOR X

 x+25+3x+5=360  210+5x=360  5x=150  X=30 SOLVE FOR X

 What does each interior angle equal in an equiangular 20-gon?  What does each interior angle equal in an equiangular n-gon?  Use this formula to find what each interior angle equals in an equiangular 40-gon. EQUIANGULAR POLYGONS

 First: Name the Polygon.  Second: Determine whether the polygon is convex or concave.  Third: Determine whether the polygon is equilateral, equiangular, regular, or neither.  Fourth: Solve for x. EXIT TICKET: (INDEX CARD) REMEMBER TO WRITE YOUR NAME! x x x x 6.1 Homework (per website/ assignment sheet) is due on Monday!