Answer:
55 degrees and 125 degrees
Step-by-step explanation:
Supplementary means that they add up to 180.
x + y = 180
Let's let x be the larger angle.
x = 15 + 2y
The above equation comes from the information given, that it's 15 more than twice the smaller angle.
Now let's use substitution.
x + y = 180
(15 + 2y) + y = 180
15 + 3y = 180
3y = 165
y = 55
The smaller angle is 55. Plug this back in to the first equation to get x.
x + y = 180
x + 55 = 180
x = 125
Now that you have both, test them again just to be sure that they fit the given conditions.