## Tuesday, December 11, 2012

### Review: Shoestring method, Heron's formula, Pythagorean Triples and Others related to Area of a triangle or polygon

Please give me feedback if there is any error or what concepts to be included for future practice tests. Thanks a lot in advance.

Online practices on finding the area of a triangle or irregular polygons.

Before trying out the online timed test, here are some reminders.

a. If the irregular polygon include the origin, then using that as a starting point for shoestring method might save some calculation time.

b. There are Pythagorean Triples hidden in lots of questions that ask for the area of a triangle given three side lengths. Thus, if you find the side length that matches the triples or multiples of the triples, it might be much easier to use that instead of heron's formula.

c. For quadrilaterals, if the diagonals are perpendicular to each other, such as rhombus, kite or others, it's much easier to use D1* D2 / 2 to get the area.

d. Sometimes breaking the polygon into different smaller parts is the easiest way to find the answer.

e. Deliberate practices are the key to steady progress.

Have fun problem solving!!