Answer:
x = 3
Step-by-step explanation:
In this piece-wise function, there are three defined sections, each for a different range of x. To find an x where y is -9, we have to set all parts of it equal to -9.
-x, x < -3
So, we can start by setting -x equal to -9 and solve for x:
-x = -9
x = 9
Our domain for this piece of the function is supposed to be x < -3. x = 9 does not fit into this range, meaning, in this range, there is no x for y = -9.
2x, -3 ≤ x ≤ -2
We can set the value 2x equal to -9 and, again, solve for x:
2x = -9
x = -4.5
The solution x = -4.5 does not fit into the defined domain of -3 ≤ x ≤ -2, therefore it is not a solution.
-x^2, x > -2
One last time, we can set -x^2 equal to -9 and solve for x:
-x^2 = -9
x^2 = 9
x = 3, x = -3
We are looking for a solution that fits into the domain, x > -2, x = -3 does not work, but x = 3 does.
In conclusion, the only solution where it fit the domain was x = 3
