Consider the system of linear equations
x
1 − x2 + (lambda)x3 = 1,

2
x1 + 2x2 + x3 = 5(lambda) + 1,
x1 + 3x2 − x3 = 4(lambda) + 2,

x1 + 7x2 − 2(lambda)x3 = 10(lambda) − 1.

1 Reduce its associated augmented matrix to row-echelon form
2 Find a value of (lambda) for which the system of linear equations is soluble
3 Solve the system of linear equations

Any assistance would be greatly appreciated!