Jawabanmu

2014-08-30T11:26:18+07:00
2014-08-30T11:28:06+07:00
Keliling = Jumlah semua sisi
K= (2x-1) + (4x +5) + (8x + 4)
50 = 2x-1 + 4x+5 + 8x+4
50=14x + 8
50-8 = 14x
x = 42 : 14
x = 3

a = 2x - 1 = 2.3 - 1 = 6 - 1 = 5
t = 4x+5 = 4.3 + 5 = 12+5 = 17
L = a x t : 2
L = 5 x 15 : 2
L = 37,5
1 2 1