Lesson 14: Alternate Interior Angles | Unit 1: Rigid Transformations and Congruence

Open Ended

Explain why the measure of angle $$ECF$$ is $$19^\circ$$ . Consider translating line $$\ell$$ by moving $$B$$ to $$C$$ .

Open Ended

What is the measure of angle $$BCD$$ ? Explain.

Multiple Choice

The diagram shows three lines with some marked angle measures: Two lines that do not intersect. A third line intersects with both lines. At the first intersection, angles are marked starting at the top right and going in the clockwise direction, 70 degrees, question mark, question mark, question mark. At the second intersection, angles are marked starting at the top right and going in the clockwise direction, 53 degrees, question mark, question mark, question mark. What are the missing angle measures marked with question marks?

• 50°, 130°, 130°
• 60°, 120°, 120°
• First intersection: 70°, 110°, 110°; Second intersection: 53°, 127°, 127°.
• 80°, 100°, 100°

Open Ended

Lines $$s$$ and $$t$$ are parallel. Find the value of $$x$$ . Explain your reasoning.

Multiple Choice

What is the scale factor that takes Figure 1 to Figure 2?

• 1
• 3
• 4
• 2

Multiple Choice

What is the scale factor that takes Figure 2 to Figure 1?

• 4
• 1
• 3
• 2

Open Ended

Lines $$AB$$ and $$CD$$ are parallel. Find the measure of angle $$BCD$$ . Explain your reasoning.

Open Ended

Lines (AB) and (CD) are parallel. Find the measure of angle (ECF). Explain your reasoning.

Open Ended

Lines $$AB$$ and $$CD$$ are parallel. Find the measure of angle $$DCF$$ . Explain your reasoning.

Multiple Choice

The diagram shows two intersecting lines. If one angle is 102°, what is the measure of angle a?

• 45°
• 78°
• 90°
• 120°