Respuesta :

ChoiSungHyun

Step-by-step explanation:

2(a + 2ab) + 4 - ab

= 2a + 4ab + 4 - ab

= 3ab + 2a + 4.

When a = 4 and b = -2,

we have 3ab + 2a + 4

= 3(4)(-2) + 2(4) + 4 = -24 + 8 + 4 = -12.