E-Math - Geometry - Find the Angles between Two Adjacent Polygons

E-Math - Geometry - Find the Angles 

between Two Adjacent Polygons

Topic: Geometry

I made another post about Finding angles of Polygons as a few of my students
had difficulty solving such questions such as the one above during the E-Math
Prelim Exams.

For i) above, the faster way to solve is to find each exterior angle by  using
\(\frac{{{{360}^o}}}{n}\;\),
 (the sum of exterior angles of any polygon is 360 degrees), then
 take\({180^o} - enterior\angle  = {\mathop{\rm int}} erior\angle \). In the solution above,
I chose to use the longer method because it is more intuitive for most of you.

In part iii) and v) above, you need to remember that in a regular polygon, besides
all interior angles being equal and all exterior angles equal, the length of every
side are also equal. When sides are equal, you can form isosceles triangles to help
you to solve the question.

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About Unknown

I created this Blog after my students told me that there is very little information about how to solve GCE O Level Math and Additional Math (A-Math) questions on the internet. Even if they manage to find, the solution were for very basic questions. I am a Full-time Math Tutor in Singapore. I tutor mainly in Northern Singapore (Woodlands, Chua Chu Kang, Bukit Panjang, Yishun and Sembawang). I also tutor in Johor Bahru.