Answer:
6+11
Step-by-step explanation:
the negative signs cancel out
Distributive property
12-3x-13 = 0
Combine like terms
-1-3x = 0
-3x = 1
Divide by -3
x = -1/3
Mrs. Blat spends at least ...
13.99 +10.00 +6.00 = 29.99
each month. Over the year, this is a minimum of
12*$29.99 = $359.88
_____
The variable cost is the cost of the 2nd book, which may or may not be purchased in any given month.
