If m ABC = 80° what is mzDBC? Justify your reasoning.
• Using the Angle Addition Postulate, 20 + m2DBC = 80. So, mzDBC = 60° using the subtraction property of equality.
Using the Angle Addition Postulate, 20 + 80 = m_DBC. So, m_DBC = 100° using the addition property of equality.
Using the addition property of equality, 20 + 80 = 100, so m_DBC = 100°.
Using the subtraction property of equality, 80 - 20 = 60, so m2DBC = 60°.

What's for breakfast? all people who ate at a certain restaurant were surveyed as to what they ordered on a particular sunday morning. 40 ate eggs 42 ate sausage 32 ate pancakes 13 ate sausage and eggs 15 ate pancakes and sausage 11 ate eggs and pancakes 6 ate all three items 3 people didn't eat any of the items how many people ate only pancakes? how many people ate at the resturant that morning? how many people didn't eat eggs?