Hello from MrBillDoesMath!
Answer:
k = 10
Discussion:
angle MYK = 180 and angle MYX = 180 => angle ZYX = 180 - 115 - 65
Trialing XYZ has 180 degrees so
180 = (4k + 5) + (6k+10) + 65 => combine like terms
180 = (4k + 6k) + (5 + 10 + 65) => as 4k +6k = 10k
180 = 10k + 80 => subtract 80 from both sides
180 -80 = 100 = 10k => divide both sides by 10
100/10 = k
Thank you,
MrB
