Final answer:
As per the equation, when the output is -3, the input is x = -8/3.
Step-by-step explanation:
To solve for x in the equation y = f(x), we can substitute the expression for f(x) into the equation:
y = 3x + 5
Now, we can isolate x by subtracting 5 from both sides of the equation:
y - 5 = 3x
To find the input when the output is -3, we can substitute -3 for y in the equation and solve for x:
-3 - 5 = 3x
-8 = 3x
x = -8/3
Therefore, when the output is -3, the input is x = -8/3.