Question 451278
Ross is six years older than twice his sister Holly's age. The difference in their ages is 18 years. How old is Holly.
..
let x = Ross' age=2y +6
let y = Holly's age
x-y=18
y=x-18
x=2y+6
x=2(x-18)+6
x=2x-36+6
-x=-30
x=30
y=x-18=0-18=12
ans:
Hollys age = 12 years
Ross' age =2y+6=24+6=30 years