Download Angle Vertex Degree Straight, Reflex, Obtuse, Acute, Right Angles

Angle Vertex Degree Straight, Reflex, Obtuse, Acute, Right Angles Supplementary Angle Complementary Angle Opposite Angle Adjacent Angle Triangle Angle Sum (Interior Angles of a Triangle) Isosceles Triangle Equilateral Triangle Exterior Angle of a Triangle Parallel lines with a transversal Corresponding Angles Alternate Interior Angles Same Side Interior Word (Short Form or Symbol) Definition (Textbook and My Own) Diagram Video or Web Resource Angle A shape, formed by two lines or rays diverging from a common point (the vertex). ∠ACB or ∠BCA Vertex • The vertex is the common point at which the two lines or rays are joined. Degree ° A unit for measuring angles, the rotation between two lines. Measurements are often expressed as a number followed by the symbol ° ∠DFE=35° ∠GFD=145° Straight Angle (=180°) ∠FDC Reflex Angle (>180°) =∠BDE Obtuse Angle (<180° and >90°) =∠CDE Acute Angles (<00°) =∠BDC Right Angle (=90°) =∠ADF Word and Short Form Definition (Textbook and My Own) Diagram Video or Web Resource Adjacent Angles Two angles that are formed when one angle is divided into two parts by a straight line. ∠BDF and ∠BDC are Adjacent Supplementary Angles (∠Supp.) Two or more angles that make 180° when they are added together. Complementary Angles (∠Comp.) ∠BDF and ∠BDC are ∠Supp. Two or more angles that together form a right angle. Opposite Angles (∠Opp.) ∠BDA and ∠BDC are ∠Comp. The angles opposite each other that are formed when two lines intersect. The angles are equal. ∠LKO and ∠JKM are ∠Opp. ∠LKJ and ∠MKO are ∠Opp. Word and Short Form Definition (Textbook and My Own) Diagram Video or Web Resource Triangle Angle Sum (rTAS) All three angles in a triangle always add up to 180°. ∠a + ∠b + ∠c =180° Isosceles Triangle (rIT) Two sides are equal and two angles are equal. The equal angles are opposite to the equal sides. Equilateral Triangle (rET) All the sides are equal and all the angles are equal. All angles equal 60°. External Angles of a Triangle (rEAT) Look at picture. The sum of the two internal angles is equal to the external angle of a triangle. ∠a + ∠b = ∠c