5. (10 points) Determine whether solutions exist for the below quadratic equation. And find the solution(s). 2x2 + x - 10 =0 6 . (10 points) A consumer's utility function is given by U(x1, X2) = X1 X2- x22 + 3x1 where x1 and x2 denote the number of items of two goods Gl and G2 that are bought. Each item costs $1 for Gl and $2 for G2. What is the "marginal rate of substitution", O x1/ x2