Suatu persegipanjang mempunyai panjang (3x+10) cm dan lebarnya (x+10) cm. Jika keliling persegipanjang tersebut 144 cm, maka panjang dan lebar persegipanjang adalah ....
6ilbert
K = 2 (p+l) 144 = 2 (3x + 10 + x + 10) 72 = 4x + 20 52 = 4x 13 = x
p = 3x + 10 = 3 . 13 + 10 = 49 l = x + 10 = 13 + 10 = 23
144 = 2 (3x + 10 + x + 10)
72 = 4x + 20
52 = 4x
13 = x
p = 3x + 10 = 3 . 13 + 10 = 49
l = x + 10 = 13 + 10 = 23
144 = (3x + 10 + x + 10) x 2
144 = (4x + 20 ) X 2
144/2 = 4x +20
72= 4x + 20
72 - 20 = 4x
52= 4x
x=52/4=13
panjang = 3.(13) + 10 = 49 cm
lebar = 13 + 10 = 23 cm
moga membantu