Isabella wants to create 23 ounces of new hand lotion, with a minimum 15% concentration of beeswax, from a mixture of two lotions.
One lotion has a 21% concentration of beeswax, and the second lotion has a concentration of 5% beeswax. Based on the inequality below, how much of the 21% lotion, x, will she need?
0.21x + 0.05(23 - x) ≥ 3.45