Answer:
k = 10
Step-by-step explanation:
The exterior angle of a triangle is equal to the sum of the two opposite interior angles.
∠ZYM is an exterior angle and
∠YZX and ∠ZXY are the 2 opposite interior angles, hence
4k + 5 + 6k + 10 = 115
10k + 15 = 115 ( subtract 15 from both sides )
10k = 100 ( divide both sides by 10 )
k = 10
