The argument is valid by the law of detachment.
Answer:

Step-by-step explanation:
Cost of one cup of coffee=$2
The original amount of money on the gift card= $30
Juan's expenses in buying coffee, after
morning are
.
The amount of money left,
, on the card
(Original amount)
(Total expenses)

Hence, the equation for,
, the amount of money remaining on the card is

Answer:
2 hours
Step-by-step explanation:
Slope represents the hourly rate.
Constant represents initial price.

If you draw out a coordinate plane you will see that they , on their Y access, are both nine witch means that they a horizontal line so all you have to do is subtract the x access witch is 3.
hope this helped