• Chapter 10 Vocabulary

    acute angle - an angle that has a measure less than a right angle

    line - a straight path of points that continues without end in both directions

    line of symmetry - an imaginary line that divides a shape into two congruent parts

    line symmetry - what a shape has if it can be folded about a line so that its two parts match exactly

    obtuse angle - an angle that has a measure greater than a right angle

    ray - a part of a line, with one endpoint, that is straight and continues in one direction

    right angle - an angle that forms a square corner and has a measure of 90°

    straight angle - an angle in which two rays point in opposite directions so that they form a straight line; has a measure of 180°


    Lesson 10.1 - Lines, Rays, and Angles

    Lesson 10.2 - Classify Triangles by Angles

    Lesson 10.3 - Parallel Lines and Perpendicular Lines

    Lesson 10.4 - Classify Quadrilaterals

    Lesson 10.5 - Line Symmetry

    Lesson 10.6 - Find and Draw Lines of Symmetry

    Lesson 10.7 - Problem Solving • Shape Patterns