Question

question 2 of 10
in the diagram below, △jkl is an equilateral triangle and (overline{km}perpoverline{jl}).
which statement must be true?
a. △jkm is a 45 - 45 - 90 triangle.
b. (km = 2cdot jm)
c. △jkm is a 30 - 60 - 90 triangle.
d. (jk = km)

Explanation:

Step1: Identify triangle type

△JKL is equilateral, so all angles 60°, sides equal. KM⊥JL makes △JKM right-angled at M.

Step2: Determine angles in △JKM

KM bisects ∠K (equilateral triangle altitude property), so ∠JKM=30°. Thus, ∠KJM=60° (180°-90°-30°).

Step3: Classify △JKM

Angles 30°, 60°, 90°: 30-60-90 triangle.

Answer:

C. △JKM is a 30-60-90 triangle.