Question

MOHON DIJAWAB YA NOMOR 18,19 , 20

Answer 1

18.
  x + 2y = 5 ↑2↓ 2x + 4y = 10
2x + 3y = 5 ↑1↓ 2x + 3y =  5 -
                                   y = 5
x + 2(5) = 5
x + 10 = 5
x = 5 - 10
x = -5
jawabannya D

19.
p =1,5 m
t =80 cm = 0,8 m
x = salah satu bambu menyilang

x² = 1,5² + 0,8²
   = 2,25 + 0,64
   = √2,89
   = 1,7 m = 170 cm
jawabannya B

20.
AB = BC = CD = AD = 6 cm
CF = 1 cm
BE = 2 cm

L persegi = 6 . 6 = 36 cm²
L Δ DCF = 1/2 . 6 .1 = 3 . 1 = 3 cm²
L Δ BEF = 1/2 . 2 . 5 = 5 cm²
L diarsir = 36 - ( 3 + 5 ) = 36 - 8 = 28 cm²
jawabannya D

maaf kalo salah :)