6. Use the Gaussian Elimination (a) to write the following augmented matrix in the reduced row echelon form and (b) use part (a) to solve for x1,x2, x3, and x4 1 1 2 0 1 2 0 3 0 1 0 2 1 0

Suppose the above equation is expressed as Ax=b with x=(x1 x2 x3)express the cofficicents of the equations in one matrix form as (A|b)

Consider the following linear equations: -2x + 4y + 10z = -5 -2x + (22-k)y+9z = -3 -2x + 4y+(12-k)z =k+9 a) Suppose the above equation is expressed as Ax = b with x = equations in one matrix form as (Alb)= -2 -2 -2 4 -2 10 4 X3 10 -5 b) Use row operations on (Alb) by substracting row 1 from row 2 and row 3 respectively. Fill in the missing entries: Express the coefficients of the -5 Submit part 3 marks Unanswered

(a) A is a 3 x 3 matrix and 2(A + I) = I. Enter det (A + I). (b) A is a 2 x 2 matrix and 2 A + 5 I = 0. Enter det (4+ I). (c) A is a 4 x 4 matrix and 42 - 4 A -21 1= 0. If det (A-21) > 0, enter det (4-21).