Answer:
[tex]\large\boxed{(f\circ g)(x)=5x+5}[/tex]
Step-by-step explanation:
[tex]f(x)=5x,\ g(x)=x+1\\\\(f\circ g)(x)=f\bigg(g(x)\bigg)-\text{put}\ x=g(x)\ \text{in}\ f(x):\\\\(f\circ g)(x)=5\bigg(g(x)\bigg)=5(x+1)\qquad\text{use the distributive property}\\\\=(5)(x)+(5)(1)=5x+5[/tex]