.
You write your equation as you read your post.
x + 17x = 180 degrees.
Everything is perfectly clear "what to do", as soon as this equation is written.
Can you complete the assignment from this point on your own ?
If you have questions, do not hesitate to ask them.
You may report me about your progress.
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To learn about supplementary angles, read the lessons
- Angles basics
- HOW TO solve problems on supplementary, complementary or vertical angles - Examples
in this site.
Consider these lessons as your handbook, textbook, guide, tutorials and (free of charge) home teacher.