Math 7, Lesson 14, Fall 2021-2022, 1/9/2022

zhenli Post in Teaching Plan
Comments Off on Math 7, Lesson 14, Fall 2021-2022, 1/9/2022

Chapter 8. Angles, triangles and quadrilaterials

1. Points, Line and Planes

  • Point: has position; has no size
  • Line: has an infinite number of points; has no width; can be determined by two points; can be straight or curved
  • Ray: a part of a line with one endpoint
  • Endpoint
  • Line segment: a part of a line between two end points; has length
  • Plane: a flat surface; has no thickness
  • Parallel lines: two lines on the same plane do not intersect (meet or cut)
  • Perpendicular (lines) to each other: two lines intersect at right angle
  • Foot of the perpendicular

2. Types of angles

  • Acute angle: angle < 90 degree
  • Right angle: angle = 90 degree
  • Obtuse angle: 90 degree < angle < 180 degree
  • Reflex angle: 180 degree < angle < 360 degree

3. Complementary, supplementary, and adjacent angles

  • Complementary angles: the sum of two angles is 90 degree
  • Supplementary angles: the sum of two angels is 180 degree
  • Adjacent angles: two angles share a common side and a common vertex but do not overlap

4. Properties of Angles

  • The sum of adjacent angles on a straight line is 180 degree
  • The sum of all angles at a point is 360 degree
  • Vertically opposite angles: when two lines intersect, the vertically opposite angles are equal

5. Home Work:

  • Handout:
    • Two pages
  • Workbook:
    • Page 45: 1, 2, 3
    • Page 46: 4, 5
« Prev: :Next »