Final answer:
The value of y is determined to be 3 by taking the absolute value of x, which is –12, and then subtracting 9, following the equation y = | x | - 9.
Step-by-step explanation:
To determine the value of y, given that x is –12 in the equation y = | x | - 9, we must first understand the absolute value function. The absolute value of a number is the non-negative value of that number without regard to its sign. Hence, the absolute value of –12 is 12.
We then substitute x with –12 into the equation: y = | –12 | - 9 which simplifies to y = 12 - 9. After doing the subtraction, we find that y = 3. So, the value of y is 3 when x is –12.