Question

1. given ∠abc and a point d in its interior. if m∠abc = 110 and m∠dbc = 45, what is the measure of ∠abd?

a) 155
b) 65
c) 75
d) 45

○ a) 155
○ b) 65
○ c) 75
○ d) 45

Explanation:

Step1: Identify angle - relationship

We know that $\angle ABC=\angle ABD+\angle DBC$.

Step2: Solve for $\angle ABD$

$\angle ABD=\angle ABC - \angle DBC$.
Substitute $\angle ABC = 110^{\circ}$ and $\angle DBC=45^{\circ}$ into the formula: $\angle ABD=110 - 45=65^{\circ}$.

Answer:

B. 65°