Area of Polygons and Circles
Topic Index | Algebra Index | Regents Exam Prep Center

Area formulas can be found at "Reference Table for Areas".

Let's pick up some hints for those more challenging problems involving area ...


 

1.

Find the area.

Be careful of problems that give "extra" information.  In this problem, the 24 is NOT needed to compute the area.


 

2.

Find the area of
parallelogram ABCD
 

When working with parallelogram problems, be sure that the height you are using is in fact perpendicular (makes a right angle) to the base (side) you are using.  In this problem, 8 is the base and 9 is the height.  The side of 10 is not used in this area.


 

3.

Find the area.

It may be necessary, when working with an obtuse triangle, to look outside the triangle to find the height.  Notice how the height is drawn to an extension of the base of the triangle.


 

4.

Find the area of the circle.  Round answer to nearest tenth.

When working with circles, be sure that you are using the radius.  In this diagram, 10 is the diameter.  The radius is half of the diameter.


 

5.

Find the area of this trapezoid.

When working with a trapezoid, the height may be measured anywhere between the two bases.  Also, beware of "extra" information.  The 35 and 28 are not needed to compute this area.

 


 
6.

Find the area of the rectangle.

Some problems may require that you find an additional piece of information BEFORE finding the area.  This problem expects you to use the Pythagorean Theorem to find the base of the rectangle BEFORE finding the area.