How to you convert a percentage into a fraction

Which of the following expressions is equal to 2x^2+8

2. using calculations based on a perpetual inventory system, determine the inventory balance altira would report in its august 31, 2021, balance sheet and the cost of goods sold it would report in its august 2021 income statement using the average cost method. (round "average cost per unit" to 2 decimal places.)

Varies inversely with x. if y=8.5 when x=-1 find x when y=-1