Question

Tolong bantu menjawab soal nomer 4 ..

Answer 1

K=2p+2l
80=2(2x-3)+2(x+7)
80=4x-6+2x+14
80=6x+8
80-8=6x
72=6x
x=72/6
x=12

semoga bermanfaat :)

Answer 2

Dik :
panjang = 2x - 3
lebar = x + 7
Keliling = 80

maka :
K = 2 x (p+l)
80 = 2x (2x-3 + x +7)
80 = 2 x (3x + 4)
80 = 6x + 8
6x = 80- 8
6x = 72
x   = 12 cm

jadi nilai x = 12 cm (C)