Answer:
Step-by-step explanation:
Mai:
She subtracted 5x instead of distributing. This is incorrect, because since it is in ( ), it has to be multiplied by 3.
Correct: 3(5x + 9) = 15x + 27
12x + 3 = 15x + 27
Noah:
Added 15x instead of subtracting. This is incorrect, because to combine like terms on each side you would add a negative number and subtract a positive number.
Correct: 12x + 3 = 15x + 27
12x - 15x = 27 - 3
-3x = 24
x = 24 / -3
x = -8
