Big Ideas Math Integrated I, 2016
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Big Ideas Math Integrated I, 2016 View details
6. Describing Pairs of Angles
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Exercise 1 Page 425

The measures of complementary angles add up to 90^(∘). The measures of supplementary angles add up to 180^(∘). Adjacent angles share a common vertex and one side.

Complementary Angles: ∠ FGK and ∠ GKL
Supplementary Angles: ∠ GKL and ∠ HGK
Adjacent Angles: ∠ FGK and ∠ HGK

Practice makes perfect

Before we take a look at the given diagram, let's start by defining complementary, supplementary, and adjacent angles.

Type of angle Description
Complementary Two positive angles whose measures have a sum of 90^(∘).
Supplementary Two positive angles whose measures have a sum of 180^(∘).
Adjacent Two angles that share a common vertex and side.
Now, let's consider the given diagram.

To determine which pair or pairs of angles are complementary or supplementary, we will add each pair to determine their sums. m∠ FGK + m∠ HGK: & 41^(∘)+ 131^(∘)=172^(∘) m∠ GKL + m∠ HGK: & 49^(∘)+ 131^(∘)=180^(∘) m∠ FGK + m∠ GKL: & 41^(∘)+ 49^(∘) =90^(∘) Having checked all of the possible pairs of angles, we can conclude which angles have which type of relationship. &∠ FGK and ∠ GKL are complementary. &∠ GKL and ∠ HGK are supplementary. Finally, ∠ FGK and ∠ HGK are adjacent angles as they share a common side KG and vertex G.