Respuesta :

mathecoach

Answer:

6 is correct

Step-by-step explanation:

[4x + 2, 8y; 7 - 2x, -7y + 8]

= [4*3 + 2, 8*1; 7 - 2*3, -7*1 + 8]

= [12 + 2, 8; 7 - 6, -7 + 8]

= [14, 8; 1, 1]

DET([14, 8; 1, 1]) = 14*1 - 1*8 = 14 - 8 = 6