What is m<1?

60
120
66
114

60 Is the correct answer

114

Step-by-step explanation:

all angles of a triangle add up to 180

180-80-34 = 66

66 is the angle right next to 1

180 degrees will be the product of both of those angles

180-66 = 114

114 degrees

proofs involving isosceles triangles often require special consideration because an isosceles triangle has several distinct properties that do not apply to normal triangles.(more about triangle types) therefore, when you are trying to prove that two triangles are congruent, and one or both triangles, are isosceles you have a few theorems that you can use to make your life easier.

step-by-step explanation:

an isosceles triangle has two congruent sides and two congruent angles. the congruent angles are called the base angles and the other angle is known as the vertex angle. ∠bac and ∠bca are the base angles of the triangle picture on the left. the vertex angle is ∠abc