Answer. 100 = X + 60
Reason is angle 100 degrees is a vertical angle to X and 60 so they will equal
So the equation is
100 = X + 60
You can solve this to check your work
Isolate x by subtracting 60 from both sides
100 = X + 60
-60 -60
___________
40 = X
Now substitute 40 for X
100 = 60 + (40)
100 = 100
They equal, it’s correct
