In Unit 5 Lesson 1 of Algebra Readiness (Pre-Algebra), students learn about pairs of angles.
An angle is formed by two rays with a common endpoint, called the vertex. In this lesson, students focus on two angles that share a common vertex and a common side, called adjacent angles.
If the non-common sides of adjacent angles form a straight line, they are called a linear pair. Linear pairs always add up to 180 degrees.
If two angles have the same measure, they are called congruent angles. Congruent angles have the same number of degrees and are denoted by the symbol ≅.
If two angles are next to each other and do not form a linear pair, they are called adjacent non-linear angles. These angles do not have any special properties beyond being adjacent.
Students will learn to identify different types of angles, measure angles using a protractor, and find missing angle measures using subtraction or addition. They will also learn how to write and solve equations involving angle measures.