ANSWER
[tex]g(x) = - 3x[/tex]
EXPLANATION
The given function is
f(x)=x
If this function is vertically stretched by a factor of 3 and flipped over the x-axis then the new function is
[tex]g(x) = - 3x[/tex]
The negative sign means there is a reflection in the x-axis.
The correct choice is A.
