Question

Given: BDis a diameter m 1 = 100° m BC= 30° m2 = 30 80 100

Answer 1

Answer:

B. 80

Step-by-step explanation:

We have been given a circle. We are asked to find the measure of angle 2.

Since BD is diameter of our given circle, so angle 1 and angle 2 will be linear pair of angles.

We know that linear angles add up-to 180 degrees, so we can set an equation as:

$m\angle 1+m\angle 2=180^{\circ}$

$100^{\circ}+m\angle 2=180^{\circ}$

$100^{\circ}-100^{\circ}+m\angle 2=180^{\circ}-100^{\circ}$

$m\angle 2=80^{\circ}$

Therefore, measure of angle 2 is 80 degrees and option B is the correct choice.

Answer 2

Answer:

∠2 = 80°

Step-by-step explanation:

Since BD is a diameter then

∠1 + ∠2 = 180°, that is

100° + ∠2 = 180° ( subtract 100° from both sides )

∠2 = 180° - 100° = 80°