Answer:
4
Step-by-step explanation:
To find the number you have to reverse the equation
Let us call the number "x"
x + 9 = 13
So to find x we flip the equation
13 - 9 = x
Solve it
4 = x
So the missing number is 4
Answer:

Step-by-step explanation:

The interval notation is (-12, 12).

The answer is c because it reflect a reflection over the x axis making it look like a M