Answer: The augmented matrix of the system of linear equations 3x1 + 4x2=10, x1+ 5x3 = 15, and -x₂ + x3 = 20 is:
[3 4 0 10]
[1 0 5 15]
[0 -1 1 20]
Step-by-step explanation: An augmented matrix is a matrix that represents a system of linear equations. It consists of the coefficients of the variables and the constants from the equations, arranged in rows and columns. In this case, the augmented matrix has three rows, one for each equation in the system, and four columns, one for each variable and one for the constant. The entries in the matrix correspond to the coefficients of the variables and the constants in the equations. For example, the entry 3 in the first row and first column corresponds to the coefficient of x1 in the first equation, and the entry 10 in the first row and fourth column corresponds to the constant on the right-hand side of the equation.