Answer:
(c) -19 + x = -21
Explanation:
You want the mathematical expression equivalent to the English sentence "a number added to -19 is -21."
Expressions
Addition is written using the math plus symbol (+).
The English word "is" usually signifies sameness or equality, expressed using the math equal sign (=).
The variable x is often used to represent "a number."
When a number is added to -19, we start with -19, then, using the plus symbol, we add x:
"a number added to -19" ⇒ -19 + x
"is" ⇒ =
"-21" ⇒ -21
So, the translated description is ...
-19 + x = -21