CPM Homework Banner
3-139.

Examine the diagram at right. Then use the information provided in the diagram to find the measures of angles and . For each angle, name the relationship that helped justify your conclusion. For example, did you use vertical angles? If not, what type of angle did you use?

Review the Math Notes box in Lesson 1.2.1.

Two increasing transversal lines, crosse two parallel lines. At the upper intersection of the left transversal: interior right is, d.  At the lower intersection of the left transversal: interior left is, c, and exterior left is 128 degrees . At the upper intersection of the right transversal: exterior right is,72 degrees.  At the lower intersection of the right transversal: interior left is, b, and exterior right is, a .