tolong bantu saya pake caranya ya

19.
s.s = 64cm^2
s^2 = 64cm^2
s = akar 64 = 8

EF^2 = AE^2 + AF^2
EF^2 = 4^2 + 4^2
EF^2 = 16 + 16
EF = akar 32 = 4 akar 2 cm

Ket: AE = AF = 1/2 s

JK^2 = FJ^2 + FK^2
JK^2 = (2 akar 2)^2 + (2 akar 2)^2
JK^2 = 4.2 + 4.2
JK^2 = 8 + 8 = 16
JK = Akar 16 = 4 cm

Ket: FJ = FK = 1/2EF

L arsir = 2 L trapesium
L arsir = 2 . 1/2 . (EG+JK) . (1/2.AE)
L arsir = 2 . 1/2 . (8+4) . (1/2 . 4)
L arsir = (8+4) . 2
L arsir = 24
Jawab: B

20.
L arsir = L segitiga
7 cm^2 = 1/2.AE.BF
AE.BF = 7 : 1/2 = 7 . 2 = 14

L Persegi Panjang = 2AE.2BF
L PP = 4(AE.BF)
L PP = 4(14)
L PP = 56 cm^2

L yg tdk diarsir = L PP - L Arsir
L yg tdk diarsir = 56 - 7 = 49 cm^2
Jawab: C

Sekian. :)
Semoga membantu.