What is the length of the line segment PQ on the coordinate grid? 
A:20 
B:30
C:40
D: 50
                                             
                                          
                                          
                                        
											 
											Answer:
B
Step-by-step explanation:
The length of segment PQ is the absolute value of the difference of the values on the x- axis , that is
PQ = | - 20 - 10 | = | - 30 | = 30 , or
PQ = | 10 - (- 20) | = | 10 + 20 | = | 30 | = 30