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CORRESPONDING ANGLE CONJECTURE

Corresponding Angle Conjecture

Definition Of Corresponding Angle Conjecture

If two parallel lines are cut by a transversal, then the Corresponding Angles are congruent.

More About Corresponding Angle Conjecture

If a transversal intersects two lines and the corresponding angles are congruent, then the lines are parallel.

Video Examples: Corresponding Angles

Example of Corresponding Angle Conjecture

EXAMPLE OF Converging Lines

In the above figure, CG||DH and AF is the transversal cutting the two parallel lines. The pairs of corresponding angles ∠ABC and ∠BED, ∠CBE and ∠DEF, ∠ABG and ∠BEH, and ∠GBE and ∠HEF are equal.

Solved Example on Corresponding Angle Conjecture

Ques: l and m are parallel lines in the figure. What are the measures of ∠x, ∠y, and ∠z?

example of  Corresponding Angle Conjecture

Choices:

A. 60°, 30° and 30°
B. 30°, 30° and 32°
C. 58°, 32° and 32°
D. None of the above
Correct Answer: C

Solution:

Step 1: From the figure, ∠x and 58°, ∠y and ∠z form corresponding angles.
Step 2: ∠x = 58° [Corresponding angles are equal.]
Step 3: ∠z + 90° + 58° = 180°
Step 4: So, ∠z + 148° = 180°
Step 5: ∠z = 180° - 148° = 32°
Step 6: ∠z = ∠y [Corresponding angles are equal.]
Step 7: ∠y = 32°

Quick Summary

  • Corresponding angles are formed when a transversal intersects two lines.
  • If the two lines are parallel, corresponding angles are congruent.
  • If corresponding angles are congruent, the two lines are parallel.
\[ ∠ABC ≅ ∠BED (where ∠ABC and ∠BED are corresponding angles formed by a transversal intersecting parallel lines) \]

🍎 Teacher Insights

Use visual aids and hands-on activities to demonstrate the concept. Have students draw parallel lines and transversals to identify corresponding angles. Emphasize the 'if and only if' relationship between parallel lines and congruent corresponding angles.

🎓 Prerequisites

  • Parallel lines
  • Transversal
  • Angle congruence
  • Basic angle types (acute, obtuse, right)

Check Your Knowledge

Q1: If two parallel lines are cut by a transversal, which of the following is true?

Q2: In a diagram where a transversal intersects two lines, ∠1 and ∠5 are corresponding angles. If m∠1 = 70°, and the lines are parallel, what is m∠5?

Frequently Asked Questions

Q: What is a transversal?
A: A transversal is a line that intersects two or more other lines.

Q: Are corresponding angles always congruent?
A: No, corresponding angles are only congruent if the two lines intersected by the transversal are parallel.

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