Apply log rule [ [tex]\text{log}_a(xy)=\text{log}_ax+\text{log}_ay[/tex] ] to condense.
[tex]\text{log}_5(2y)+\text{log}_5(8)=\text{log}_5(2y*8)[/tex]
→ [tex]\text{log}_5(16y)[/tex] ←
Best of Luck!