Input (x-value)
Output (y-value)
You need to find the x-value that produces a y-value of -1. Since you know:
y = -1 Use the rule, and substitute/plug this into the equation
y = -2x + 33 Plug in -1 for "y" in the equation since y = -1
-1 = -2x + 33 Subtract 33 on both sides
-1 - 33 = -2x + 33 - 33
-34 = -2x Divide -2 on both sides to get "x" by itself
17 = x
An input of 17 yields an output of -1