The image of positive scale function y = - 2x is shifted one unit length to the left, and the analytic expression of the function is?

The image of positive scale function y = - 2x is shifted one unit length to the left, and the analytic expression of the function is?

Level: this question x = X-1, substituting y = y, x = x + 1 into the original function, then the new function after translation is y = - 2 (x + 1) = - 2x-2
Vertical: X does not change, move up n, y = y + N, y = y-n, x = x, substitute into the original function
Left plus right minus, bottom plus minus. That is to say, the X or y after moving is added or subtracted into the original function