Proofs involving Triangles with complete solution
exterior angle of a triangle (Model 1)
An angle formed by one side of a triangle and the extension of an adjacent side of the
triangle. 1
remote interior angles (Model 2)
With respect to an exterior angle, the two interior angles of the triangle that are not
adjacent to the exterior angle.
auxiliary line (Model 3)
A line introduced in a figure to make a proof possible.
corollary (Model 4)
A statement that is easily proved by applying a theorem.
Angles 4 and 5 form what type of angles?
vertical angles
Given the following diagram, find the required measure.
Given: l | | m
m 1 = 140°
m 3 = 50°
m2=
40
Given the following diagram, find the required measure.
Given: l | | m
m 1 = 140°
m 3 = 50°
m4=
130
Given the following diagram, find the required measure.
Given: l | | m
m 1 = 140°
m 3 = 50°
m5=
40
Given the following diagram, find the required measure.
exterior angle of a triangle (Model 1)
An angle formed by one side of a triangle and the extension of an adjacent side of the
triangle. 1
remote interior angles (Model 2)
With respect to an exterior angle, the two interior angles of the triangle that are not
adjacent to the exterior angle.
auxiliary line (Model 3)
A line introduced in a figure to make a proof possible.
corollary (Model 4)
A statement that is easily proved by applying a theorem.
Angles 4 and 5 form what type of angles?
vertical angles
Given the following diagram, find the required measure.
Given: l | | m
m 1 = 140°
m 3 = 50°
m2=
40
Given the following diagram, find the required measure.
Given: l | | m
m 1 = 140°
m 3 = 50°
m4=
130
Given the following diagram, find the required measure.
Given: l | | m
m 1 = 140°
m 3 = 50°
m5=
40
Given the following diagram, find the required measure.
