Answer:
Ivy is 6 years old and Rose is 12 years old.
Step-by-step explanation:
To solve this problem, two variables are necessary since we have two unknown variables: Ivy's age and Rose's age.
Ivy's age will be
and Rose's age will be
"Ivy is half as old as her sister":
this will be our <u>fist equation.</u>
"In six years, Ivy will be two-thirds as old as Rose"
in six years Ivy will have years, and Rose will have
years, so for this sentence we have the equation:
this will be our <u>second equation.</u>
Substituting the value of x from the first equation into the second, and solving for y(Rose):
Rose is 12 years old.
and Ivy (using the fist equation):
Ivy is 6 years old.