Jawab yang nomer 12 ,13,14 pakai cara

12. sisi = 6
 keliling = 4*s =4 *6 =24 cm (b)
13. L =540
lebar= 12
L = p*l
540 = p * 12
p = 540/12 =45cm (a)
14. L = 1/2 * A*T = 1/2 * 17 *8
= 68CM (A)