The measure of ∠ABD is 60° and the measure of ∠ABC is 155°. What is the measure of ∠DBC ?

(1 point)

A. 215°

B. 180°

C. 95°

D. 155°

1 answer

To find the measure of ∠DBC, we can use the fact that the angles around point B must add up to 360°.

We know:

  • ∠ABD = 60°
  • ∠ABC = 155°

To find ∠DBC, we can first find the measure of ∠ABO using: \[ \text{Measure of angle around point B} = ∠ABD + ∠ABC + ∠DBC = 360° \]

Rearranging this gives: \[ ∠DBC = 360° - (∠ABD + ∠ABC) \]

Substituting the values we have: \[ ∠DBC = 360° - (60° + 155°) = 360° - 215° = 145° \]

It appears there was a miscalculation because none of the options provided matches this.

Alternatively, if you are interpreting the angles as parts of a straight line (and given the information):

Then consider the relation: \[ ∠ABC = ∠ABD + ∠DBC \]

Then we can rearrange to find: \[ ∠DBC = ∠ABC - ∠ABD = 155° - 60° = 95° \]

Thus, the correct measure of ∠DBC is C. 95°.