mohn bntuan yaaaa.............

Mapel : Matematika
Kelas : VII SMP
Bab : Perbandingan

Pembahasan :
Ri = Ro + 5

1/x = 1/Ri + 1/Ro
1/x = 1/(Ro + 5) + 1/Ro
1/x = (Ro + Ro + 5)/(Ro² + 5Ro)
1/x = (2Ro + 5)/(Ro² + 5Ro)
x = (Ro² + 5Ro)/(2Ro + 5)
10 = (Ro² + 5Ro)/(2Ro + 5)
20Ro + 50 = Ro² + 5Ro
Ro² - 15Ro - 50 = 0
Ro = 18 hari

Ri = Ro + 5
Ri = 23 hari