The angle sum theorem states that the sum of all the interior angles of a triangle is 180 degrees. In a Euclidean space, the sum of the measure of the interior angles of a triangle sum up to 180 degrees, be it an acute, obtuse, or a right triangle which is the direct result of the angle sum theorem of the triangle
Answer:
not enough info it's just saying that the sides with II are equal and the ones with I are equal
Answer:
Step-by-step explanation:
Triangle ABC is an equilateral triangle, then:
=> angle ABC = angle BAC = angle ACB = 60 deg
AB // CE, according to alternative interior pair of angles theorem:
=> angle ACE = angle BAC = angle ABC = 60 deg (1)
B, C, and D are colinear, then:
angle ECD + angle ACE + angle ACB = 180 deg
=> angle ECD = 180 - angle ACE - angle ACB = 180 - 60 - 60 = 60 deg (2)
From (1) and (2):
=>angle ACE = angle ECD = 60 deg
