Post your question in the Comment section below, and a GRE expert will answer it as fast as humanly possible.
- Video Course
- Video Course Overview
- General GRE Info and Strategies - 7 videos (free)
- Quantitative Comparison - 7 videos (free)
- Arithmetic - 42 videos
- Powers and Roots - 43 videos
- Algebra and Equation Solving - 78 videos
- Word Problems - 54 videos
- Geometry - 48 videos
- Integer Properties - 34 videos
- Statistics - 28 videos
- Counting - 27 videos
- Probability - 25 videos
- Data Interpretation - 24 videos
- Analytical Writing - 9 videos (free)
- Sentence Equivalence - 39 videos (free)
- Text Completion - 51 videos
- Reading Comprehension - 16 videos
- Study Guide
- Philosophy
- Office Hours
- Extras
- Prices
Comment on Octagon Angle
For this one, I found the
Great reasoning, Marlon!
Great reasoning, Marlon!
Yes, that technique will always work. Here's why.
We know that the sum of the angles in an n-sided polygon = 180(n - 2)
So, if we have a REGULAR n-sided polygon, the measurement of each angle = 180(n - 2)/n
Now take: 180(n - 2)/n
Expand to get: (180n - 360)/n
Rewrite as: 180n/n - 360/n
Simplify: 180 - 360/n
In your solution, you take 360/n and subtract this from 180 degrees.
In other words, the measurement of each angle = 180 - 360/n, which is the same as the expression we derived from the formula.