Respuesta :

Answer:

Her error was multiplying -3 and -4 which gives +12 but she wrote -12 instead

Step-by-step explanation:

Mariana workings:

-3(2x - 4) = -12

-6x - 12 = -12

Her error was multiplying -3 and -4 which gives +12 but she wrote -12 instead

-6x = 0

x=0

Correct workings:

-3(2x - 4) = -12

-6x + 12 = - 12

-6x = -12 - 12

-6x = -24

x = -24/-6

x = 4