Question

Persegi panjang punya panjang ( 2x-3) cm & lebar ( x +8) cm.keliling 82. maka panjang persegi panjang...

Answer 1

Dik :
panajng = 2x-3
lebar = x+8
K = 82 cm

maka :
K = 2 x (2x-3 + x + 8)
82 = 2 x (3x+5)
82 = 6x + 10
6x = 82-10
x  = 72/6
x = 12 cm

maka :
Panjang = 2x - 3 = 2(12) - 3 = 21 cm
Lebar = x + 8 = 12 + 8 = 20 cm

Answer 2

Keliling = 2(p +l)
82 = 2(2x -3 +x +8)
82 = 2(3x +5)
82 = 6x +10
82 -10 = 6x
72 = 6x
x = 72/6
x = 12

Maka,
panjang = 2x -3
             = 2(12) -3
             = 24 -3
             = 21 cm

Itu jawabannya.