What’s That Angle? You will be given the measure of an angle and asked to find either the complement or supplement. The winner moves on, the loser sits. First we practice. What’s the angle – automatic, directions on click Complement of 15° Supplement of 25°

Complement of 40° Supplement of 140° Complement of 10° What are the numbers of the quadrants?

Complement of 37° Supplement of 125° Complement of 68° What are the numbers of the quadrants?

Honors Geometry Warm-up: Today: Work on your entrance ticket-> on the desk in back. Today: HW Questions? 1.6 Instruction Test Friday! 2 problems on the unit exam directly from this, find the area of a triangle and square on a coordinate system Honors Addition: know more names of polygons, shoelace method?

1.6 Two-Dimensional Figures   Objective: Identify and name polygons. Find perimeter, circumference, and area of two-dimensional figures.

Can we name polygons from 3 to 10 sides? Concept

vocabulary convex – no side line goes through the polygon nonconvex or concave – a polygon that is not convex – a side line goes through the polygon (connect the dots) equilateral – polygons with all sides congruent equiangular – polygons with all angles (interior) congruent regular – a polygon that is both equiangular and equilateral 5.4

EXAMPLE 1 A. Name the polygon by its number of sides. Then classify it as convex or concave and regular or irregular. Answer: quadrilateral, convex, irregular Example 1

EXAMPLE 1 B. Name the polygon by its number of sides. Then classify it as convex or concave and regular or irregular. Answer: nonagon, concave, irregular Example 1

EXAMPLE 1 A. Name the polygon by the number of sides. Then classify it as convex or concave and regular or irregular. A. triangle, concave, regular B. triangle, convex, irregular C. quadrilateral, convex, regular D. triangle, convex, regular Example 1a

EXAMPLE 1 B. Name the polygon by the number of sides. Then classify it as convex or concave and regular or irregular. A. quadrilateral, convex, irregular B. pentagon, convex, irregular C. quadrilateral, convex, regular D. quadrilateral, concave, irregular Example 1b

AREA and Perimeter…..? Tell me what you know!

Concept

Example 2 A. Find the perimeter and area of the figure. Answer: Perimeter = 13.8 cm Area = 10.58cm² A. REVERSE. Find the length and width of the rectangle is the length is twice as long as the width. With total area 72 ft². Answer: Length = 12ft Width = 6ft Example 2

EXAMPLE 2 B. Find the circumference and area of the figure. Give the exact value. Answer: C = 8p ≈ 25.1 in A = 16p ≈ 50.3 in² Example 2

Real World EXAMPLE 3 Terri has to mark an area in the classroom where the students may read. Which of these shapes has the greatest area that would allow her for the most space? A square with side length of 5 feet B circle with the radius of 3 feet C right triangle with each leg length of 6 feet D rectangle with a length of 8 feet and a width of 3 feet Square A = 25 sq. ft. Circle A ≈ 28.3 sq. ft Triangle A = 18 sq. ft Rectangle A = 24 sq. ft Read the Test Item------What should we do? Example 3

EXAMPLE 4 Find the perimeter and area of a pentagon ABCDE with A(0, 4), B(4, 0), C(3, –4), D(–3, –4), and E(–3, 1). Perimeter Answer: AB = 4√2 BC = √17 CD = 6 DE = 5 EA = 3√2 PABCDE = 11 + 7√2 + √17 u ≈ 25.0 u To find the area, I would use Box & triangles (subtracted) and shoelace method Area Answer: AABCDE = 41.5 u2 Example 4

Shoelace Method 2 123.5 u2 (6, 20) (19, 7) (3, 4) 6 20 380 19 7 42 21 EXAMPLE 5 Shoelace Method 6 20 380 19 7 42 21 3 4 76 24 60 425 178 2 123.5 u2 (19, 7) (3, 4) First use the 3 triangles, than use the shoelace method to see that they are the same.

107 sq. u. Shoelace Method 107 u2 (19, 20) (2, 16) (13, 6) 13 6 114 19 260 40 2 16 304 208 12 362 576 107 u2 (13, 6)

Assignment Due tomorrow: 1.6 P.61-64 #13,16,18, 29-32,34,36,50 1.6 More Practice Test Friday!