TOLONG CANTUMKAN CARANYA jika x+y = 100 dan x/y = 1/9 , maka x-y ?

SPLDV

x + y = 100
x/y = 1/9
x - y ?

x/y = 1/9
kali silang
y = 9x
substitusi

x + 9x = 100
10x = 100
x = 10

y = 9(10)
= 90

x - y
= 10 - 90
= -80