Answer the blanks:

m∠a = 50m

∠acb = 85

answer blank #1: find ∠adc

answer blank #2: find ∠ cdb

answer blank #3: find ∠ acd

answer blank #4: find ∠ bcd

answer blank #5: find ∠ b

use only numbers. do not label your answers.

1. 90°

2. 90°

3. 40°

4. 45°

5. 45°

Step-by-step explanation:

Given: ΔABC,

CD⊥AB,

m∠A=50°,

m∠ACB=85°

Solution:

1. ∠ADC is a right ange, because CD⊥AB, so

2. ∠CDB is a right ange, because CD⊥AB, so

3. Consider triangle ACD. The sum of the measures of all interior angles is always 180°, so

4. By Angle Addition Postulate,

5. Consider triangle ABC. The sum of the measures of all interior angles is always 180°, so

step-by-step explanation:

answer: option a.

step-by-step explanation:

you know that the quadrilateral opqr ( a four sided figure) is inscribed in circle. this means that all its vertices are on the circle.

then, by definition, the opposite angles of the quadrilateral are supplementary, this means that the sum of their measures is 180 degrees.

you can observe in the figure that the angles ∠opq   and the angle ∠orq   are opposite, therefore:

then, can be used to d to calculate the measure of ∠opq