Question

Which of the following transformations are linear?

A. y1 = -5x1, y2 = 9x1, y3 = 8x1

B. y1 = (x2^(2)) , y2 = x3 , y3 = x1

C. y1 = 4x2, y2 = -8x3, y3=-2x1

D. y1 = 7x1 - 9x2 + 5x3, y2 = 10x2 -3x3, y3= -4x1 - 6x2

E. y1 = x1 + 10 , y2 = x2

F. y1 = 3, y1 = 6, y3 = 4