Question

1. what is the missing statement?

statement	reasons
	definition of complementary angles

type a response

Explanation:

Step1: Recall complementary - angle definition

By the definition of complementary angles, if two angles are complements, the sum of their measures is 90 degrees.

Step2: Write the statement

The missing statement is $\angle1+\angle2 = 90^{\circ}$

Answer:

$\angle1+\angle2 = 90^{\circ}$