Question

z-common core algebra i b-crconsider the following sets.u = {all triangles}e = {x|x ∈ u and x is equilateral}i = {x|x ∈ u and x is isosceles}s = {x|x ∈ u and x is scalene}a = {x|x ∈ u and x is acute}o = {x|x ∈ u and x is obtuse}r = {x|x ∈ u and x is right}which is a subset of i?○ e○ s○ a○ r

Explanation:

A subset means all elements of one set are in another. An equilateral triangle has 3 equal sides, so it meets the definition of an isosceles triangle (at least 2 equal sides). Scalene triangles have no equal sides, so they are not isosceles. Acute, right, and obtuse describe angle measures, not side lengths, so these sets include triangles that may not be isosceles.

Answer:

E