how do i solve this math problem?

Question

Given: Ray OP and Ray OR trisect angle NOS. the measure of angle NOP is 3x-4y, the measure of angle POR is x-y, and the measure of angle ROX is y-10. how do i find the measure of angle ROS???

Answer 1

3x - 4y = x - y
x - y = y - 10
x = 2y - 10
6y - 30 - 4y = y - 10
y = 20
ROS = 10