Sergio did not use 15 inches of his yellow yarn
        
             
        
        
        
Answer:
X=4
Step-by-step explanation:
The solution is in the file
 
        
                    
             
        
        
        
Carmen has given 6 coins to her brother<span />
        
             
        
        
        
You plug in the values for x in each respective equation.
a) f(3) = 3 + 1 which equals: 4. 
so, f(3) = 4
b) g(3) = (3)^2 - 3 which equals 9 - 3, which equals 6.
so, g(3) = 6.
hope this helps! (: