Grades 8-12 
Mathematics 
Geometry 
Standard 20

Students know and are able to use angle and
side relationships in problems with special
right triangles such as 30-60-90 triangles
and 45-45-90 triangles.
 
 
Resources
Lesson Plans
Assessments

Geometry 
Larson/Boswell/Stiff, 1995,  
D.C. Heath and Company 

Section References 
9.4 Special Right Triangles 

Specific Textbook   
Web Sites   

http://www.glencoe.com/  
sec/math/prealg/mathnet/   

http://www.eduplace.com/  
links/   

http://www.eduplace.com/   

http://www.hmco.com/  
college/mathematics/  
index.html   

http://www.mcdougallittell  
.com/   

http://www.hmco.com/   

http://www.SRA-4KIDS.com/   

General Math   
Reference Sites   

http://www.learner.org/  
sami/view-category.php3  
?category=math   

http://www.score.k12.ca.us/   

http://henson.austin.apple  
.com/edres/curric.shtml   

http://school.discovery.com/  
schrockguide/index.html   

http://www.EDsOasis.org/   

http://www.math.com/   

http://www.nea.org/grants/  
free.html   

http://www.wcom.com/  
marcopolo/   

http://www.udel.edu/sine/   

http://dewey.chs.chico.k12  
.ca.us/math.html   

Free Stuff   

http://www.nea.org/  
grants/free.html   

State/National Math   
Ed Organizations   

http://www.nctm.org/   

http://www.cde.ca.gov/   

Calif. Dept. of Ed. Standards, Assessment, Ed. Reference.   

Calculator Reference Site   

http://www.ti.com/  
calc/docs/calchome.html 



Previously Published Data 

1.) Students will draw a 45-45-90 triangle; measure the sides; find the ratios of the legs to the hypotenuse; and compare their results with their classmates. 


2.) Students will draw a 30-60-90 triangle; measure the sides; find the ratios of the legs to the hypotenuse; and compare their results with their classmates. 
3.) Students will use the Pythagorean Theorem to find the relationship for all 30-60-90 and 45-45-90 triangles.
 

Previously Published Data 

1.) Students will find the length of all three sides of a 45-45-90 triangle, given the length of any one side.