keliling persegi panjang = 308 .Jika panjang = (8x -6)meter dan lebar = (6x -8)meter,tentukan luasnya

2(8x - 6) + 2(6x - 8) = 308.
 16x - 12 + 12x - 16 = 308.
               16x + 12x = 308 + 12 + 16.
                         28x = 336.
                             x = 336 : 28.
                             x = 12m
Panjang = 8x - 6 = ( 8 x 12) - 6 = 96 - 6 = 90m.
Lebar = 6x - 8 = (6 x 12) - 8 = 72 - 8 = 64m.
Luas = Panjang x Lebar = 90 x 64 = 5760m².
Maaf kalo salah...
Semoga membantu :))

keliling = 2 (p + l)
308 = 2 (8x - 6 + 6x - 8)
308 = 2 (14x - 14)
308/2 = 14x - 14
154 = 14x - 14
14x = 154 + 14
14x = 168
x = 168/14
x = 12

p = 8x - 6
p = 8(12) - 6
p = 96 - 6
p = 90 cm

l = 6x - 8
l = 6(12) - 8
l = 72 - 8
l = 64 cm

luas = p × l
= 90 × 64 cm²
= 5760 cm²