BY : ANA JULIA ROGOZINSKI -A polygon is a shape with three or more -Polygons can be classified sides; a closed figure made by joining according to the number line segments . of sides it has. Polygons Not polygons -Each segment that forms a polygon is a side of a polygon. The common endpoints of 2 sides is a vertex. A segment that connects any two nonconsecutive vertices is a diagonal. -You can describe a polygon by comparing the length of its sides or the measure of its angles. Name of polygon Number of sides Triangle 3 Quadrilateral 4 Pentagon 5 Hexagon 6 Heptagon 7 Octagon 8 Nonagon 9 Decagon 10 Undecagon 11 Dodecagon 12 Tell whether the figure is a polygon or not. If it is classify it by the number of sides it has. 2. NO 1.Yes, and it’s an octagon 3.Yes, it is a triangle -A concave polygon has one vertex pointing inward. -A convex polygon has all vertices pointing outward. Tell if each shape is concave or convex. 1. Concave 2. Convex 3. Concave All the sides are the same (congruent). All the angles are the same (congruent). A regular polygon is both of them. Tell if each shape is equiangular, equilateral or a regular polygon? 1.equiangular 2. Regular 3. Equilateral - This theorem states that any time you add up 1 side you add 180 to the sum it needs to sum. 1. 2. Find the interior angles of a triangle. (3-2)180 1 x 180= 180 180 / 3 = 60 Find the interior angles of a nonagon. (9-2) 180 7 x 180= 1260 1260 / 9 = 140 3. Find the interior angles of a pentagon. (5-2) 180 3 x 180 = 540 540 /3 = 180 Theorem 6-2-1: Converse: If a quadrilateral is a parallelogram, then its opposite sides are congruent B A M C D If the opposite sides of a quadrilateral are congruent, then it is a parallelogram. V L 1. AB is congruent to CD T Tell whether it is a parallelogram or not? NO YES 2. MV is congruent to TL 3. BC is congruent to DA 4. ML is congruent to VT YES Theorem 6-2-2 If a quadrilateral is a parallelogram, then its opposite angles are congruent. Converse: If the opposite angles in a quadrilateral are congruent, then it is a parallelogram. 1.<A is congruent to <D 2.<B is congruent to <C 3. To what angle would <M be congruent to? <N Theorem 6-2-3: If a quadrilateral is a parallelogram, then its consecutive angles are supplementary. Converse: If the consecutive angles of a quadrilateral are supplementary, then it is a quadrilateral 1. 2. 3. 4. m<A + m<B = 180 m<C + m<D = 180 m<B + m< D = 180 Would measurement of angle A and angle D be supplementary ? NO, because they are not consecutive angles and they don’t sum 180 Theorem 6-2-4: If a quadrilateral is a parallelogram, then it’s diagonals bisect each other? Converse: If the diagonals of a quadrilateral bisect each other then it is a parallelogram. 1. AO is congruent to DO 2. CO is congruent to BO 3.What can you tell in this diagonals? That DM is congruent to BM and that AM is congruent to CM - A parallelogram is a quadrilateral that has opposite sides parallel to each other or it has two pair of parallel lines. 1. Opposite sides are congruent 2. Opposite angles are congruent 3. Consecutive angles are supplementary 4. Diagonals bisect each other 5. A quadrilateral that has a opposite sides parallel to each other. 6. One set of congruent and parallel sides. Tell whether you each figure is a parallelogram or it isn’t. 1.No 3.Yes 2. Yes -A square is a parallelogram that is both a rectangle and a rhombus meaning that all its sides are congruent and all the angles have the same measurement. (It is a regular polygon). 1. 4 congruent sides and angles 2. Diagonals are congruent and perpendicular. 1. How can you tell by the diagonals that the figure is a square? --You can tell it is a square by the diagonals being perpendicular and congruent. Tell whether it is a square NO YES A rhombus is a parallelogram with 4 congruent sides. - 1. Diagonals are perpendicular -6-4-3: If a quadrilateral is a rhombus, then it is a parallelogram. -6-4-4: If a parallelogram is a rhombus, then its diagonals are perpendicular -6-4-5: If a parallelogram is a rhombus, then each diagonal bisects a pair of opposite angles. Tell whether it is a rhombus? YES YES NO - A rectangle is a parallelogram with 4 right angles. 1. Diagonals are congruent -6-4-2:If a quadrilateral is a rectangle , then it is a parallelogram. -6-4-2: If a parallelogram is a rectangle, then its diagonals are congruent. 1. What can you say about the diagonals of this triangle? That AC is congruent to BD If side MN = 12 and side ML = 5, what is the length of the other two sides? 2.LO = 12 3. NO= 5 -A square is both a rectangle and a rhombus together including all its properties. A rectangle has 4 congruent angles and diagonals are congruent while a rhombus has all 4 congruent sides and diagonals are perpendicular. - A trapezoid is a quadrilateral with one pair of parallel sides. - Is a trapezoid with a pair of congruent legs. 1. Diagonals are congruent 2. Base <‘s are congruent 3. Opposite ,’s are supplementary -6-6-3: If a quadrilateral is an isosceles trapezoid then each pair of base angles are congruent. -6-6-4:If a trapezoid has one pair of congruent base angles then the trapezoid is isosceles. -6-6-5:A trapezoid is isosceles if and only if its diagonals are congruent. E F 2. YB is parallel to EF 3. YB is parallel to MT Y M B T - A kite has two pairs of adjacent sides. 1. Diagonals are congruent 2. One pair of congruent angles (the ones formed by non-congruent sides) 3. One of the diagonals bisects the other. -6-6-2: If a quadrilateral is a kite, then its diagonals are perpendicular. -6-6-2: If a quadrilateral is a kite, then exactly one pair of opposite angles are congruent. 1. < R is congruent to <P 3. The diagonals of the kite are intersecting at right angles. 2. It has two pairs of congruent consecutive sides.