In Exercises 15 and 16, fill in the missing entries of the matrix, assuming that the equation holds true for all values of the variables.

In Exercises 15 and 16, fill in the missing entries of the matrix, assuming that the equation holds for all values of the variables. X1 2x1 - 4X2 X2 X1 - X3 15. X3 -X2 + 3x3 ? 3x1 - 2x2 X1 X1 + 4x2 16. ? ? X2 X2