Answer:
I think it's the second formula.
Explanation:
Let x be the original price.
The discount rate is 20%
Sale Price is $68.90
Discount = 20% of x = 0.2x
Using the formula, Sale Price = Original Price - Discount,
Original Price - Discount is x-0.2x = 0.8x
$68.90 = 0.8x
From here on, just do the equation :) Hope this helps!