PSAT Math : How to find the length of a side of a polygon
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Example Questions
Example Question #1 : Other Polygons
If the following shape was going to be drawn in a circle, what is the minimum radius of the circle?
10
8
9
7
11
7
IF you draw the longest diagonal across the shape, the length of it is 13.4. This means the radius must be at least 6.7. The answer is 7.
Example Question #13 : Other Polygons
Note: Figure NOT drawn to scale.
The above polygon has perimeter 190. Evaluate 
To get the expression equivalent to the perimeter, add the lengths of the sides:
Since the perimeter is 190, we can simplify this to
and solve as follows:
Example Question #101 : Plane Geometry
Note: Figure NOT drawn to scale.
The perimeter of the above polygon is 225. Also, 
Evaluate 
Insufficient information exists to answer the question.
To get the expression equivalent to the perimeter, add the lengths of the sides:
Since the perimeter is 225, we can simplify this to
and, furthermore, since 
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