When solving a system of equations, how do you determine which method to use?

Ingredient c: 1/4 cup for 2/3 serving or ingredient d: 1/3 cup for 3/4 serving which unit rate is smaller

What is the solution of the equation? 35√(x+2)3+3=27

Which account has the highest effective annual interest rate? not necessary but show how you got your answer.a. account 1: interest is compounded quarterly at an annual rate of 4.20%.b. account 2: interest is compounded monthly at an annual rate of 4.15%.c. account 3: interest is compounded semiannually at an annual rate of 4.10%d. account 4: interest is compounded annually at a rate of 4.25%.