Which sentence is true about equilateral triangle . A. only 2 sides are the same length

B. only 2 angels have the same measure

C. Each side is a different length

D. All sides are the same length

E. Each angel has a different measure

Actually Welcome to the concept of Equilateral triangles.

Since, from the name itself, equilateral triangles have all sides and angles equal.

Hence the correct answer is

==> D. All sides are the same length.

step-by-step explanation:

points a and b are equidistant from the desired line, so the line you find by using them will go through point r.

using points other than a and b will give the desired line only if they are equidistant from r. if they are randomly located, the perpendicular line you create will not necessarily go through point r, hence will not be a solution to the problem.