Respuesta :

Answer:

See below for answers and explanations

Step-by-step explanation:

Part A

10x - 12x - 3 does not equal -5x. Looks like what she did wrong was treating -3 as -3x and got her incorrect result that way

Part B

10x - 12x - 3 = (10-12)x - 3 = -2x - 3
you can’t combine a number with a variable and a number without a variable

-2x-3