Answer
a. $2x+3$, b. $-10x-1$
Work Step by Step
We are given that $f(x)=-4x+1$ and $g(x)=6x+2$.
We know that $(f+g)(x)=f(x)+g(x)$ and $(f-g)(x)=f(x)-g(x)$.
Therefore:
$(f+g)(x)=(-4x+1)+(6x+2)=-4x+6x+1+2=2x+3$.
$(f-g)(x)= (-4x+1)-(6x+2)=-4x-6x+1-2=-10x-1$