Tolong Dibantu yaaa...

a) keliling = 2(p+l)
= 2((3x-4)+(x+1))
= 2(4x-3)
= 8x-6
b) keliling = 8x-6
34 = 8x-6
34+6=8x
5=x
panjang =(3 x 5)-4 = 11cm