Question

Sebuah persegi panjang berukuran panjang (5x - 1) cm dan lebar (2x +2) cm. Jika keliling persegi panjang itu 72cm, maka panjang dan lebarnya adalah

Answer 1

K = 2.p +2.l 72 = 2.(5x -1) + 2.(2x + 2) 72 = 10x -2 + 4x + 4 72 = 10x + 4x -2 + 4 72 = 14x + 2 72-2 = 14x X = 70/14 = 5 Panjang = (5.5 - 1 ) = 24 Lebar = (2.5 + 2) = 12

Answer 2

2(p+l) =k
2(5x-1+2x+2) = 72
2(7x+1) = 72
14x + 2 = 72
14x      = 70
x          = 5

panjang = 5x-1 = 5(5)-1 = 24 cm
lebar = 2x+2 = 2(5)+2 = 12 cm