Answer:
k = 10
Step-by-step explanation:
∡ZYX = 180° - 115° = 65° (angles in a line add up to 180°)
*∡ stands for angle.
∑ of ∡Z , Y and X should be equal to 180° (angles in a triangle add up to 180°)
∴ (4k + 5)° + 65° + (6k + 10)° = 180°
10k + 80 = 180
10k = 100
k = 100 ÷ 10 = 10
