Answer:
There was 62.23% change in radius as the ion formed.
Step-by-step explanation:
 
        
             
        
        
        
One way is to factor it
trial and error, with experience
(3x+5)(x-2)
answer is C
        
                    
             
        
        
        
Similar to the other question, because AB is parallel to CD, you know the 72º angle corresponds to the angle on top of y.
Because that angle above y and y together make a straight line (and a straight line measures 180º), you have
72 + y = 180
Solving that for y, you get y = 108º
        
             
        
        
        
What am i solving exactly?
        
             
        
        
        
The sum is 27 you just need to add them all together