Jawaban:
Panjang = 27 cm
Lebar = 13 cm
Penjelasan:
Diketahui
Keliling = 80cm
Panjang = 5x + 2
Lebar = 2x + 3
2×(p+l)
2×(5x+2 + 2x+3)
2×(7x+5)
14x+10 = 80
14x = 80-10
14x = 70
x = 70/14
x = 5
Panjang = 5x + 2
= 5(5)+2
= 27cm
Lebar = 2x +3
= 2(5)+3
=13cm