Depending on what the number is in for the bag
        
             
        
        
        
Answer:
12
Step-by-step explanation:
12 divided by 1 using long division is 12. As long as a number is divided by 1 the number is the same as the dividends number. 
 
        
                    
             
        
        
        
When writing the equation keep in mind that 7 + x is said as a term that is squared so it has to be squared while it's still together; (7 + x)².
 
        
             
        
        
        
A fact family is a group of math facts using the same numbers. In the case of addition/subtraction, you use three numbers and get four facts. For example, you canform a fact family using the threenumbers 10, 2, and 12: 10 + 2 = 12, 2 + 10 = 12, 12 − 10 = 2, and 12 − 2 = 10.
        
             
        
        
        
Let Casey's age be x
Brian's age will be -3 from 2 times x ( Casey's age ) so it will be 2x-3
Adam's age will be Casey's age (x) + 9 which is x+9
NOW the sum of all these ages is 46 so..
Casey's age + Brian's age + Adam's age = 46
x + 2x-3 + x+9 = 46
2x + x + x + 9 -3 = 46
4x + (9 - 3) = 46
4x - 6 = 46
now transfer the numbers on the left one by one to the other side( right )
4x = 46 - 6        ( always remember the sign of the number becomes the                            opposite when we transfer them to other side)
4x = 40
x = 40 / 4
x = 10
so x = Casey's age = 10
2x - 3 = Brian's age = 2 * 10 - 3
                                 = 20 - 3   =   17
x + 9 = Adam's age = 10 + 9 = 19