Answer
$(f-g)(-1)=-4$
Work Step by Step
Given is:
$$f(x)=x^2+3$$
$$g(x)=-2x+6$$
Since $(f-g)(x)=f(x)-g(x)$, then:
$$(f-g)(x)=x^2+3-(-2x+6)$$
$$(f-g)(x)=x^2+3+2x-6$$
$$(f-g)(x)=x^2+2x-3$$
Substitute $x=-1$ into the equation:
$$(f-g)(-1)=(-1)^2+2(-1)-3$$
$$(f-g)(-1)=1-2-3=-4$$
