Answer
$f'(x)= 5.2$
Work Step by Step
$(h+g)' = h' +g'$
therefore
lets choose,
$h(x) = 5.2x$
$g(x) = 2.3$
$f(x)=5.2x+2.3=h(x)+g(x)$
$f'(x)=(h(x)+g(x))'=h'(x)+g'(x)$
and $\frac{d}{dx}(c)=0$ therefore $\frac{d}{dx}(2.3)=0$
and $\frac{d}{dx}(x^{n})=nx^{n-1}$ therefore $\frac{d}{dx}(5.2x)=5.2\times x^{0}=5.2\times 1=5.2$
meaning
$h'(x)=5.2$
$g'(x)=0$
So,
$f'(x)= h'(x)+g'(x) = 5.2 + 0 = 5.2$