Answer:
x = 19
Step-by-step explanation:
x-42+x-32+180-x+17 = 180
3x +123 = 180
3x = 57
x=19
x = 91.
Putting 91 into the two equations inside the triangle makes the angles 59 and 49, and makes the outside angle 108. Those two angles must add and equal the outside angle, and they do, meaning x = 91.