Answer: $8.99
============================================
Work Shown:
x = price of one jump rope before the discount
x-1.80 = price of one jump rope after discount
2*(x-1.80) = total amount Gavin spends
2*(x - 1.80) = 14.38
x - 1.80 = 14.38/2 .... divide both sides by 2
x - 1.80 = 7.19
x = 7.19 + 1.80 ..... adding 1.80 to both sides
x = 8.99
Before the sale, one jump rope costs 8.99 dollars
After the sale, one jump rope costs 8.99 - 1.80 = 7.19 dollars.
This doubles to 2*7.19 = 14.38 dollars which is what Gavin spent in total. This helps confirm the answer.