Answer:
2x + h
Step-by-step explanation:
[tex]\frac{f(x+h)-f(x)}{h}[/tex]
= [tex]\frac{(x+h)^2+38-(x^2+38)}{h}[/tex]
= [tex]\frac{x^2+2hx+h^2+38-x^2-38}{h}[/tex]
= [tex]\frac{2hx+h^2}{h}[/tex]
= [tex]\frac{h(2x+h)}{h}[/tex] ← cancel h on numerator/ denominator
= 2x + h
