Math Problem Statement

Two parallel lines are cut by a transversal. Given that m∠5 = 139°, find m∠2 and m∠4.

Solution

In the image, two parallel lines are cut by a transversal, and you are asked to find the measures of angles 2\angle 2 and 4\angle 4, given that the measure of 5=139\angle 5 = 139^\circ.

Here’s how we can solve it using angle relationships for parallel lines and a transversal:

  1. Corresponding Angles:

    • 5\angle 5 and 1\angle 1 are corresponding angles, so m1=139m \angle 1 = 139^\circ.
  2. Alternate Interior Angles:

    • 1\angle 1 and 2\angle 2 are alternate interior angles, which means they are congruent. So, m2=139m \angle 2 = 139^\circ.
  3. Linear Pair:

    • 4\angle 4 and 5\angle 5 form a linear pair. Linear pairs are supplementary, meaning the sum of their measures is 180180^\circ. Therefore, m4=180139=41m \angle 4 = 180^\circ - 139^\circ = 41^\circ.

Final Answer:

  • m2=139m \angle 2 = 139^\circ
  • m4=41m \angle 4 = 41^\circ

Let me know if you need further clarification or details.


Here are 5 related questions to deepen understanding:

  1. How would you identify alternate exterior angles in the same diagram?
  2. If m6m \angle 6 was given, how could you find m3m \angle 3?
  3. What is the relationship between corresponding angles in parallel lines cut by a transversal?
  4. Can you explain how vertical angles relate in this diagram?
  5. If m3=80m \angle 3 = 80^\circ, what would be the measure of m7m \angle 7?

Tip: Remember that corresponding and alternate interior angles are congruent when parallel lines are cut by a transversal. This simplifies finding unknown angles.

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Parallel lines
Transversals
Angles
Corresponding Angles
Alternate Interior Angles

Formulas

Linear Pair: m∠A + m∠B = 180°

Theorems

Alternate Interior Angles Theorem
Corresponding Angles Postulate
Linear Pair Theorem

Suitable Grade Level

Grades 7-9