How do you mix compounds to achieve equipotent mixtures?

Let’s say we need 50 µL of the mixture, IC₅₀ of compound A is 1 nM and IC₅₀ of compound B is 10 nM. In that case we take 25 µL of compound A and 25 µL of compound B. The total of 50 µL is subsequently diluted to generate the dose response curve. Since the compounds are equally effective, 25 µL of compound A can be added to 25 µL of compound B without a ‘dilution effect’.