Answer:
x=20 degrees
Step-by-step explanation:
because this is a supplementary angle, you add everything and set it equal to 180 degrees. so it would be x + 100 + 3x = 180. combine like terms to get 100 + 4x = 180. subtract 100 from both sides to get 4x = 80. divide by 4 on both sides to isolate the x and your final answer is 20. hope this helped! good luck in school xoxo
