< Questic Use the echelon method to solve the following system of two equations in two unknowns. Check your answer. 7x+3y=-28 6x-3y=-24 Select the correct choice below and, if necessary, fill in the answer box to complete your choice. OA. The solution is (Type an ordered pair.)" OB. There are infinitely many solutions. The general solution is (y), where y is any real number. OC. There is no solution.