1. Write the augmented matrix for the system of equations and use it to solve the system *+X, + X =1 X - X, +3x. = -8 2x1 + 2x, + x, =3 2. Determine if b is in Span ( a, , a, , a, } . Justify your answer. 4 a, = a, = 1 -2 .b= -5 3 6 3 12