Answer:
The original cost for 1 pound of coffee is $4.50, and Gabriel wants to buy 4 pounds, so the total cost without the coupon would be:
4 pounds x $4.50/pound = $18
With the coupon, Gabriel can subtract $2 from the final amount, so the total cost with the coupon would be:
$18 - $2 = $16
Therefore, Gabriel would have to pay $16 to buy 4 pounds of coffee with the coupon.
To write an expression for the cost to buy p pounds of coffee, we can use the formula:
cost = price per pound x number of pounds - coupon
If Gabriel buys at least one pound of coffee, then the expression would be:
cost = $4.50p - $2
So the cost to buy p pounds of coffee can be calculated by plugging in the desired value for p into this expression.