Digits, Grade 8, Volume 1, Homework Helper

7-6: Additional Problem Solving

Part 1

Example Finding Angle Measures Using Parallel Lines

In the diagram, a||b and c||d. If m∠1 = 60°, what is m∠6?

Solution

  • Method 1 ∠2 and ∠1 are corresponding angles formed by parallel lines a and b and transversal c, so they are congruent. Congruent angles have equal measures, so m∠2 = 60°.

    ∠4 and ∠2 are corresponding angles formed by parallel lines c and d and transversal b, so they are congruent. Congruent angles have equal measures, so m∠4 = 60°.

    intersecting parallel lines.

    ∠4 and ∠6 form a straight angle, so they are supplementary angles.

    table with 3 rows and 1 column , row1 column 1 , m angle 4 plus m angle 6 equals 180 degrees , row2 column 1 , 60 degrees plus m angle 6 equals 180 degrees , row3 column 1 , m angle 6 equals 120 degrees , end table


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Table of Contents

Digits, Grade 8, Volume 1, Homework Helper Unit A: Number and Operations Unit B: Proportionality Unit C: Expressions, Equations, and Relationships English/Spanish Glossary Formulas Math Symbols Formulas Measures Properties