10. Solve the system of equations in integers x + 2y + z = 1 3x+y+2z3 x+7y+2x=1 11. Determine whether the following non-homogenous system of equation has a solution or not. x+2y+z 3w = 1 2x+4y+3z + w = 3 3x+6y+4z2w = 5 12. Determine the condition for which the system x+y+z = b 2x+y+32b+1 5x+2y+az b = admits (i) only one solution, (ii) no solution, (iii) infinitely many solutions.