Question

identifying angle pair relationships
use the diagram to identify the special angle pairs.
∠adc and ∠bdc are
a pair of complementary angles is angles

Explanation:

Step1: Identify linear - pair angles

Linear - pair angles are adjacent angles that form a straight line. $\angle ADC$ and $\angle BDC$ are adjacent and their non - common sides form a straight line. So, $\angle ADC$ and $\angle BDC$ are linear pairs.

Step2: Identify complementary angles

Complementary angles are two angles whose sum is $90^{\circ}$. $\angle ECA$ and $\angle ACB$ (assuming the right - angle at $C$ for the complementary pair; since they can add up to $90^{\circ}$ if the right - angle is considered as a sum of two angles formed by a ray splitting it)

Answer:

$\angle ADC$ and $\angle BDC$ are linear pairs. A pair of complementary angles is angles $\angle ECA$ and $\angle ACB$ (assuming the right - angle at $C$ is split into these two angles)