G-CO.9 (Mathematics)
            Standard Identifier:
            
                G-CO.9
            
        
        
            Content Area:
            
                Mathematics
            
        
        
            Grade Range:
            
                8–12
            
        
            
                Domain:
                
                    Congruence
                
            
                    
                Discipline:
                
                    Geometry
                
            
                    
                Conceptual Category:
                
                    Geometry
                
            
        
        Cluster:
Prove geometric theorems. [Focus on validity of underlying reasoning while using variety of ways of writing proofs.]
Standard:
Prove theorems about lines and angles. Theorems include: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment’s endpoints.
    Prove geometric theorems. [Focus on validity of underlying reasoning while using variety of ways of writing proofs.]
Standard:
Prove theorems about lines and angles. Theorems include: vertical angles are congruent; when a transversal crosses parallel lines, alternate interior angles are congruent and corresponding angles are congruent; points on a perpendicular bisector of a line segment are exactly those equidistant from the segment’s endpoints.
                Questions: Curriculum Frameworks and Instructional Resources Division |
                CFIRD@cde.ca.gov | 916-319-0881