Question 1204984
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Answer:  <font color=red size=4>(-1, 4)</font>


Reason


y=-f(x) tells us "reflect f(x) over the horizontal x axis"
This is because we're flipping the y or f(x) outputs from positive to negative, or vice versa.


A point like (-1,-4) flips to <font color=red>(-1, 4)</font>
The x coordinate stays the same.
The y coordinate flips from -4 to 4. 



An example:
{{{
drawing(400,400,-5,5,-5,5,
graph(400,400,-5,5,-5,5,-100,4x,-4x),
circle(-1,-4,0.05),circle(-1,-4,0.07),circle(-1,-4,0.09),circle(-1,-4,0.11),circle(-1,-4,0.13),circle(-1,-4,0.15),circle(-1,4,0.05),circle(-1,4,0.07),circle(-1,4,0.09),circle(-1,4,0.11),circle(-1,4,0.13),circle(-1,4,0.15),

locate(-1-1.6, -4-0.2, "(-1,-4)"),
locate(-1-1.2, 4-0.2, "(-1,4)")
)
}}}
{{{f(x) = 4x}}} in green
{{{g(x) = -f(x) = -4x}}} in blue



Another example:
{{{
drawing(400,400,-5,5,-5,5,
graph(400,400,-5,5,-5,5,-100,-4^(-x),4^(-x)),
circle(-1,-4,0.05),circle(-1,-4,0.07),circle(-1,-4,0.09),circle(-1,-4,0.11),circle(-1,-4,0.13),circle(-1,-4,0.15),circle(-1,4,0.05),circle(-1,4,0.07),circle(-1,4,0.09),circle(-1,4,0.11),circle(-1,4,0.13),circle(-1,4,0.15),

locate(-1-1.6, -4-0.2, "(-1,-4)"),
locate(-1-1.2, 4-0.2, "(-1,4)")
)
}}}
{{{f(x) = -4^(-x)}}} in green
{{{g(x) = -f(x) = -( -4^(-x) ) = 4^(-x)}}} in blue


Use graphing tools Desmos or GeoGebra to try out other examples. 
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