In the given figure, the angles ∠ABC and ∠DBC are complementary angles, which means they add up to 90 degrees. Therefore,
∠ABC + ∠DBC = 90 degrees
Substituting the given angle measures, we get:
45° + ∠DBC = 90°
Subtracting 45 degrees from both sides, we get:
∠DBC = 45 degrees
Therefore, the measure of angle ∠DBC is 45 degrees.