Help me #pleaseeeeeeeeeeeeeeeee

[tex]l=p-3 \\ K=2(p+l) \\ 34=2(p+p-3) \\ 34=2(2p-3) \\ 34=4p-6 \\ 40=4p \\ p=10 \\ l=p-3 =10-3=7[/tex]