6. By using the substitution v = 4x y, solve the quation v = (4x y). (7 marks) - 1- e#+c A. y(x) = 4x 2( - 1+ e*+c - ex+c B. y(x) = 4x + 2 ( 1+ ex+c - eT+c C. y(x) = 2 D. y(x) = 2 1- e+c %3D 1+ e*+c ex+c 7. Solve the initial value problem using Laplace transforms y" 6y - 6y = 0, y(0) = 2, y'(0) = 1. (7 marks) %3D A. y(t) =D De3t-e- B. y(t) =D De3t + e-2 2t %3D C. y(t) = te3t + t-?e-2t D. y(t) = t?e3t t-2e-2t %3D