Etta and Moorea run a stand where they sell lemonade and brownies. Their cost function is \(C(Q_{L}, Q_{B})= .50Q_{L}+0.25Q_{B}+Q_{L}^{2}+Q_{B}^{2}-Q_{L}Q_{B}\) They can sell a cup of lemonade for $1.20 and a brownie for $0.95. What are Moorea and Etta's profit-maximizing sales quantities for each product?

I found that

MCL= .50+2QL+QB

MCB= .25+2QB+ QL

1.20=.50+2QL+QB

.95=.25+2QB+QL