Answer:
k = 10°
Explanation:
According to the exterior angle theorem, the exterior angle will be equal to the two opposite inside angles added together. It will look like the following, and we solve for k from there.
115° = (4k + 5)° + (6k + 10)°
115° = 4k° + 5° + 6k° + 10°
115° = 6k° + 4k° + 10° + 5°
115° = 10k° + 15°
100° = 10k°
10° = k
k = 10°